Acupuncture has been widely used to treat cognitive impairment after traumatic brain injury (TBI). But its efficiency has not been scientifically and methodically evaluated. The objective of this study is to evaluate the efficiency and safety of the acupuncture treatment for cognitive impairment after TBI in adults.This protocol of systematic review will be conducted in accordance with the Preferred Reporting Items for Systematic Review and Meta-analysis Protocols. We will conduct the literature searching in the following electronic databases: the Cochrane Library, MEDLINE, EMBASE, Web of Science, Springer, the Chinese Science Citation Database (CSCD), China National Knowledge Infrastructure (CNKI), the Chinese Biomedical Literature Database (CBM), Wanfang, and the Chinese Scientific Journal Database (VIP). The time limit for retrieving studies is from establishment to November 2021 for each database. All published randomized controlled trials related to this review will be included. Review Manager (V.5.3.5) will be implemented for the assessment of bias risk and data analyses. The selection of the studies, data abstraction, and validations will be performed independently by 2 researchers.This review will assess the clinical efficacy and safety, as well as the acupoints characteristics of acupuncture on CI of TBI in adults.This review will summarize the current evidence of acupuncture on CI of TBI outcomes and provide guidance for clinicians and patients to select acupuncture for CI of TBI in adults.This protocol of systematic review has been registered on INPLASY website (No. INPLASY2021110113). Approximately 155 people die each day in the US from injuries that include a TBI.Traumatic brain injury (TBI) is among the significant causes of morbidity and mortality in the present world.,7 Cognitive symptoms include deficits in attention, executive functioning, memory , language, visuoperceptual functioning, and psychomotor functioning abilities.–10 Cognitive deficits can significantly impair activities of daily living (ADL), employment, social relationships, recreation, and active participation in the community. Cognitive rehabilitation is a confluence of therapeutic activities based on brain–behavior relationships. Cognitive rehabilitation includes methods such as remediation, compensation, and holistic or multimodal programs.,13Cognitive symptoms are an especially common and important area of concern for TBI survivors, with a majority of individuals with moderate-to-severe TBI having persistent and marked cognitive impairment (IC) at 1 to 5 years post-injury. Nowadays, acupuncture has been widely used clinically by doctors of traditional Chinese Medicine, neuropsychiatric disorder to treat IC of traumatic brain injury with satisfied efficacy.–18 However, no relevant review or protocol has been published to date. Therefore, it is necessary to conduct evidence-based review to evaluate the efficacy and safety of acupuncture for FC in adults. It is urgently needed to accomplish this review.Acupuncture therapy is an external therapy used in traditional Chinese medicine that has been using as an alternative nonpharmacological therapy that involves the insertion of needles into acupuncture points in the skin as to correct imbalances of the flow of Qi through meridians.2https://inplasy.com/?s=INPLASY2021110113. The protocol will be strictly developed under the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocols, and Cochrane Handbook for Systematic Reviews of Interventions.The protocol for this review has been registered in the International Platform of Registered Systematic Review and Meta-analysis Protocols (INPLASY) (registration number: INPLASY2021110113) on November 30, 2021. Available online: 2.12.1.1As the randomized controlled trials (RCTs) are reliable and feasible, RCTs will be included only. After the research, published clinical trials that reported the efficacy and safety on acupuncture for IC of TBI will be included. Literature of non-RCTs, case reports, animal research, meta-analyses, reviews, and retrospective studies will be excluded.2.1.2Patients aged ≥18 years and diagnosed with IC of TBI according to Montreal cognitive assessment scale (MoCA) <26 will be included, without limits on age, gender, nationality, race, and medical units.2.1.3We will include the studies using acupuncture as the sole intervention in the experimental group, while we have no restrictions on intervention in the control group. Studies involving acupuncture combined with other therapies will be included if the other therapies are used equally in both the experimental and control groups.2.1.4The main outcomes of this review include Montreal cognitive assessment scale (MoCA). Additional outcomes of this review include Mini-mental State Examination (MMSE), and Barthel index (BI).2.22.2.1The electronic databases of the Cochrane Library, MEDLINE, EMBASE, Web of Science, Springer, the Chinese Science Citation Database (CSCD), China National Knowledge Infrastructure (CNKI), the Chinese Biomedical Literature Database (CBM), Wanfang, and the Chinese Scientific Journal Database (VIP) will be searched from the establishment to July 1, 2020. All published RCTs on this subject will be included. Exemplary search strategy of MEDLINE is listed in Table Relevant keywords were used to create search strategies, as listed in Table The MEDLINE search strategy in Table 2.32.3.1Two reviewers (NL and XA), who will be told the aim and process of the system review, will select the trials and studies independently according to the criteria for inclusion by reading the titles and abstracts; if necessary, the full text will be read for further assessment. The discrepancies in the process will be discussed and solved using RHW. Details of the research choices are shown and exclusive studies will be listed and explained. The process of study selection will be presented in Preferred Reporting Items for Systematic Reviews and Meta-Analyses flow diagram Fig. . To ensu2.3.2An electronic form will be established via Excel to extract substantial contents, and then filled by 2 reviewers independently. Information was extracted from the qualified articles by using a standardized data extraction form as follows: authors’ name, country, year of publication, study design, gender, and age of patients, intervention, sample size, outcomes, adverse events, and follow-up. Disagreements will be solved by group discussion or consult seniors. However, if we fail to reach a consensus, the authors of trials will be contacted for further details and verification.2.3.3If any data information is not sufficient in the included trials, we will try to contact the first or corresponding author by phone or email, requesting adequate information and details of the studies included to retrieve missing or insufficient trial data. However, if the author is not available or sufficient information cannot be obtained, we will have a group discussion and analysis based on the current information. Meanwhile, the potential impact of missing data will be taken into account, and a relative discussion will be presented in the result section.2.3.4Two independent authors assess the risk of bias of each included article according to the Cochrane Handbook for Systematic Reviews of Interventions. The methodological quality will be evaluated from the following domains: random sequence generation, allocation concealment, blinding of participants, and therapists, blinding of outcome assessment, incomplete outcome data, selective reporting, and other biases. The judgements on these items will be categorized as “high risk of bias”, “low risk of bias”, or “unclear risk of bias”. Discrepancies will be resolved by negotiation or by consulting other reviewers.2.3.5Dichotomous data and continuous variables are included in the outcomes of interest, and we will use the risk ratio (RR) to express dichotomous data and use mean difference (MD) to assess differences in the continuous outcomes between the groups. Although different methods for the measurement of outcomes are used in different trials, we will choose standardized mean difference (SMD) if they have the same outcomes. The corresponding 95% confidence interval (CI) for each parameter will be calculated between the electroacupuncture treated group and the control group. We will choose a descriptive review if quantitative synthesis is not appropriate.2.3.6P < .5 will be defined as statistically significant between studies. The heterogeneity of studies will be evaluated by I2 statistic. The following criteria will be used: I2 < 50% will be deemed as low heterogeneity; I2 between 50% and 75% will be considered as moderate heterogeneity; I2 > 75% will be considered as high heterogeneity.The research will be performed with RevMan 5.3.5 software. 2.3.7When heterogeneity is high, we will perform a subgroup analysis based on different controls, intervention time, treatment frequency, follow-up duration, and outcome measurements. We will also tabulate the adverse reactions and then perform an evaluation.2.3.8If possible, a sensitivity analysis will be performed to verify the robustness of the review conclusions. The impact of methodological quality, sample size, and missing data will be assessed. In addition, the analysis will be repeated after the exclusion of low methodological quality studies.3IC of TBI is one source of distress. This disease has brought physical, psychological, and economic burdens to many people in many countries and has brought great suffering. It has aroused more and more concern all over the world. As an important part of traditional Chinese medicine, Acupuncture has been widely used in clinical practice, especially in the treatment of nervous system diseases, for its various therapeutic techniques and remarkable curative effects. Now, Acupuncture has become more and more widely used in IC of TBI because it is a relatively straightforward, safe, and cheap therapy, compared with other conventional therapies. But at the present, there is no systematic evaluation report on its therapeutic effectiveness and safety for the treatment of IC of TBI.The protocol of this systematic review study aims to assess the efficacy, safety, and cost benefits of acupuncture in the treatment of IC of TBI in adults. Meanwhile, we have tried our best to search and found that no relevant systematic review and meta-analysis concerning this topic has been reported in the last 5 years, and we will integrate the latest and most comprehensive clinical evidence in this field, hoping to offer a greater variety of treatment options for patients with IC of TBI and inspire more peer experts and doctors to carry out as many relevant studies as possible in the future.Conceptualization: Na Li, Ruihui Wang.Data curation: Na Li, Xia Ai, Xinrong Guo, Juan Liu, Dong Wang, Lei Sun, Rongchao Zhang.Investigation: Xinrong Guo.Methodology: Na Li, Xia Ai.Validation: Ruihui Wang.Visualization: Na Li.Writing – original draft: Na Li, Xia Ai.Writing – review & editing: Ruihui Wang, Lei Sun.


Moderating effects revealed that age and sex do not significantly moderate the relationship between social media use and everyday emotion in COVID-19. Given the nature of social media among international students, who are also prone to suffering from anxiety and depression associated with social media use, the positive effect of social media use and everyday emotion, especially in COVID-19, has important implications for international students’ education stakeholders. Thus, gaining a deeper understanding of this relationship could enable them to harness social media and use it as a valuable tool to overcome the social distancing constraints in COVID-19.Social media has become a valuable tool in providing an opportunity to stay in touch with one’s social networks, providing reassurance and practical advice to individuals to pre-empt panic and rumors in COVID-19. However, the implications of social media use on the everyday emotion (anxiety and depression) of users especially, international students, are not well understood. Thus, this study sought to examine the impact of social media use on the everyday emotion of international students in China during COVID-19. Using a structured online questionnaire based on modified questions from the generalized anxiety disorder 7 (GAD-7) and the Patient Health Questionnaire 9 (PHQ-9) and social media use instruments, data were collected from 480 participants. Of the total responses received, 474 were further analyzed employing the Partial Least Squares Path Modelling (PLS-PM). This study showed a significant positive relationship between social media use and everyday emotion ). Additionally, self-rated anxiety and depression associated with social media use among international students were generally mild ( Since its emergence, social media has been instrumental in the everyday activities of individuals in various aspects of their lives, including personal communication, business development management, and networking.In risk communication during health crises, the use of social media as a source of delivering and receiving health information alerts, conveying public opinions and attitudes on issues related to infectious diseases, public health, and behavioral medicine has, over the past decade, expanded tremendously ,2,3. SinAmong the popular groups of people familiar with social media is the youth, specifically, students studying abroad. Undoubtedly, international students use social media to socialize, educate, and constantly communicate with their families and friends . PreviouRegardless of the enormous benefit derived from the use of social media, especially among international students in the hit of the pandemic, some studies have shown that spending extra hours on social media may pose behavioral threats of addiction, depression, and anxiety ,16,17. SThe study of Bontcheva et al., 2013, and Roth and Brönnimann, 2013, opined that, due to the incidence of information overload or misinformation in the use of social media, users might tend to have increased mental health problems ,22. GlobDespite the existence of a handful of these studies into the effect of social media use on users’ mental health, none of those studies have focused on the impact of social media use on the everyday emotions of international students in the COVID-19 pandemic. Thus, there is the need to examine the impact social media use has on the everyday emotion (anxiety and depression) of international students in COVID-19.Anxiety is a physiological state consisting of cognitive, somatic, emotional, and behavioral components . The comResearch into the impact of social media use on users has produced mixed results over the years. On the one hand, social media use has been found to increase self-esteem, improve general well-being, enhance social support, reducing anxiety and depression stressors, and provide overall life satisfaction ,34,35,36Over the years, several psychotherapy tools have been introduced to assess and treat generalized anxiety disorder (GAD) and depression among individuals. One of such tools is cognitive-behavioral therapy (CBT). Cognitive-behavioral therapy has over the years become the “go-to” tool for treating several conditions and disorders, including antisocial behaviors , anxiety disorders, depression, eating disorders , and general stress. Several studies have also documented CBT use in treating sleep disorders such as insomnia, excessive daytime sleepiness, etc. ,38,39. CAs previous studies have found the use of social media during COVID-19 to impact everyday emotion (anxiety and depression), this study categorizes these emotions into the physiological, cognitive, behavioral, and emotional domains, which are consistent with the CBT model. The decision to use the CBT model stems from the fact that it is combinatory. It combines cognitive and behavioral therapies and has strong empirical evidence for treating mood and anxiety disorders ,42,43.Though the CBT model is a treatment tool, it is essential to identify and categorize everyday emotions relating to social media use into the CBT categories. This will help determine whether or not social media use impacts the various domains of CBT, i.e., physiological, behavioral, cognitive, and emotional domains, differently. Therefore, this study uses CBT as an identification tool rather than a therapeutic tool.Four key domains interact within the human environment: the physiological domain made up of one’s biology, genetics, physical, and physiological attributes, and the behavioral domain characterized by an individual’s action and behavior. The cognitive domain consists of thoughts, cognitions, beliefs, and self-talk, while the emotional domain is made up of one’s feelings, moods, and emotions. Because an individual’s thoughts, feelings, actions, and physiological characteristics are so closely intertwined, any effects or changes in any of these domains impact others. Hence, adopting a more holistic approach to examining the impact social media use has on all these domains and, consequently, users’ everyday emotion is essential .An individual’s anxiety and depression are triggered by several factors acting as stressors. Studies have found demographic factors such as age and sex to correlate with social media use . PreviouFurthermore, sex has also been found to be crucial in the study of social media use and everyday emotion. For instance, studies have found a high combined use of social media and information technology to be associated with an increased risk of prolonged stress and symptoms of depression among women ,49. OtheHypothesis 1 (H1).International students’ social media use has a significantly positive effect on their everyday emotions in COVID-19.Hypothesis 2a (H2a).Age has a significantly positive effect on international students’ everyday emotions in COVID-19.Hypothesis 2b (H2b).Age significantly moderates the relationship between international students’ social media use and their everyday emotion in COVID-19, such that the higher the age of a user, the weaker the relationship.Hypothesis 3a (H3a).Sex  has a significant effect on international students’ everyday emotions in COVID-19.Hypothesis 3b (H3b).Sex significantly moderates the relationship between international students’ social media use and their everyday emotion in COVID-19, such that the differences in the category of sex weaken the relationship between social media use and everyday emotions.The model in A structured online questionnaire consisting of questions adapted and modified from the General Anxiety Disorder-7 (GAD-7) instrument ,53 and Phttp://www.surveyhero.com (accessed on 27 January 2020)), an online survey content management portal, setting restrictions such that respondents could answer the questions only once.The questionnaire was developed in English using SurveyHero , a sample size of 200 is considered to be fair and 300 as good ,58,59,60Data from questionnaires were exported from the online survey content management portal into Microsoft excel for cleaning and imported into IBM SPSS Statistics version 23 and Intellectus Statistics online software for statistical analysis. The data analysis included descriptive and partial least squares path modeling (PLS-PM model) analysis.Cronbach’s alpha was used to test the reliability of the various constructs using the guidelines suggested by George and Mallery, 2018, where >0.9 is excellent, >0.8 is good, >0.7 is acceptable, >0.6 is questionable, >0.5 is poor, and ≤0.5 is unacceptable .The PLS-PM model was assessed by evaluating the validity of the measurement model and the structural model. After model validation, the regressions of the PLS-PM were analyzed.The measurement model (outer model) was assessed by examining the unidimensionality, loadings, communalities, and cross-loadings of the indicator variables. Bootstrapping was also used to check the significance of each loading.Unidimensionality of Indicators. For reflective indicators, the latent construct must be positively correlated with each indicator. If the latent variable increases in value, then each indicator should also increase. Sanchez (2013) defines this as the unidimensionality of indicators . CronbacFactor Loadings and Communality. The factor loadings and communalities were examined for the reflective indicators to identify indicators with weak loadings for the latent variables. The variability in each indicator should explain at least 50% of its latent variable construct  ,63,64. OCross-Loadings. The cross-loadings were also examined for the reflective indicators to assess the validity of the model. A cross-loading occurs when an indicator has a higher absolute loading on a different latent variable than the one to which it is assigned ,64,65.Bootstrapping. Bootstrapping was performed with 500 resamples. The loadings were assessed for the reflective indicators, and the weights were examined for formative indicators. Significance was determined using 95% confidence intervals for the given parameter estimates, which were calculated based on an alpha value of 0.05 ,63,64.2-values for each endogenous variable, the average variance extracted (AVE) for each latent variable with reflective indicators, and the goodness of fit (GoF) index for the model. Bootstrapping was also used to determine the reliability of the inner model.The structural or inner model was assessed by examining the R2-values. The R2-values were calculated for each endogenous variable to determine if the relationships among the latent variables were appropriate. Each endogenous variable should have an R2-values ≥ 0.20 [Rs ≥ 0.20 .Average Variance Extracted. The average variance extracted for each construct was calculated to verify whether each latent variable had a strong relationship with its reflective indicators. Each latent variable should have an AVE ≥ 0.50, which suggests that 50% or more of the variance for the indicators is explained by its latent variable ,63,64. A2-values and average commonality for each latent variable. Values greater than 0.90 are considered a good model fit, while a GoF index less than 0.90 and greater than 0.70 is an acceptable model fit [Goodness of Fit. The GoF index was used to assess the predictive power of the PLS-PM. The GoF index was calculated by computing the geometric mean of the average Rodel fit ,63. A moBootstrapped Regression Paths. Bootstrapping was performed with 500 resamples. The regression coefficients were evaluated using 95% confidence intervals to determine the significance of the regression paths using an alpha value of 0.05 ,63,64.Bootstrapped Moderating Effects. Bootstrapping was performed with 500 resamples. Moderation was evaluated using the two-stage approach to create each interaction term from the latent variable scores . The modn = 154, 32.50%). The majority of the respondents were pursuing their bachelor’s degree  at the time of this study. The majority of respondents were residents in Zhenjiang , while the most frequently observed category of sex was Male . Furthermore, the most frequently observed category for the number of years resident in China was two years . Finally, the result showed that the most frequently observed category for nationality was Ghana, with a total number of respondents .The demographic distribution of the respondents is presented in n = 249, 52.50%), while the most reported level of depression was also MILD .The overall anxiety and depression ratings of social media users in COVID-19 as assessed using the GAD-7 and PHQ-9 measuring instruments are presented in A Cronbach alpha coefficient was calculated for the various scales used to assess the impact of social media on everyday emotion, consisting of GAD-7, PHQ-9, and social media use.The items for the GAD-7, PHQ-9, and social media use scales had Cronbach’s alpha coefficients of 0.85, 0.76, and 0.79, respectively, indicating an excellent internal reliability compared to other studies ,66. TablA partial least squares path modeling (PLS-PM) analysis was conducted to determine whether the latent variables, social media use, everyday emotion, sex, and age, adequately described the data. The goal of PLS-PM is to describe the network of variables and their relationships accurately. The PLS-PM model diagram can be seen in Unidimensionality of Indicators. All latent variables exhibited unidimensionality, indicating the relationships between the latent variables and indicators were appropriate for PLS-PM. The unidimensionality assumption did not apply to latent variables with only one indicator variable. The Cronbach’s alpha and Dillon-Goldstein’s rho statistics are presented in Factor Loadings and Communality. Cross-Loadings. Bootstrapping. Each reflective manifest variable had a significant loading, suggesting that its latent variable explains a substantial portion of each reflective indicator. Since there were no formative indicators, the bootstrapped weights were not examined. The table of the inner model summary is presented in 2-values. 2-values for the endogenous latent variable; emotion was 0.14, which is considered a weak explanatory power [Rry power .Average Variance Extracted. As presented in Goodness of Fit. The GoF index, GoF = 0.31, indicates that the model had a poor model fit and poor prediction ability.Bootstrapped Regression Paths. Social media use significantly predicted everyday emotion, B = 0.34, 95% CI . Age was also found to significantly predict everyday emotion, B = 0.12, 95% CI . Additionally, there was a statistically significantly relationship between the category of sex and everyday emotion ). Thus, hypotheses H1, H2a, and H3a were supported. Bootstrapped Moderating Effects. Regarding the moderating effects, this study found that sex and age did not significantly moderate the effect social media use had on everyday emotion , B = −0.04, 95% CI ), respectively; thus, not satisfying H2b and H3b. This study aimed to evaluate the impact of social media use on everyday emotion (anxiety and depression) of international students during the outbreak of the COVID-19 pandemic. The study found a significant positive impact of social media use on everyday emotions of international students, as shown in Studies on the effect of social media use on anxiety and depression have had, over the years, reported mixed results. While some studies have shown that social media provides benefits such as enabling individuals to express their thoughts and feelings and receive social support ,69,70, oAt a critical time such as this, when quarantining and social distancing are becoming the norm in several parts of the world ,71, sociThe use of social media among international students may have presented students with the opportunity to provide reassurance and practical advice within their social networks to pre-empt panic and rumors ; hence, Conversations on social media present a unique opportunity to promote the awareness of COVID-19, its symptoms, and the possible effects of institutional decisions such as quarantine measures and the development of COVID-19 vaccines. This information keeps international students informed; thus, reducing the stressors and fears caused by COVID-19. Studies on information use and social media use have shown that a lack of information in crucial times could increase tension, causing anxiety and depression . AdditioThis study found a significantly positive correlation between all the constructs; behavioral domain, physiological domain, cognitive domain, and emotional domain of international students. These findings are consistent with previous studies ,76,77 thSex and age were introduced into the model to test their moderating effect on the relationship between social media use and everyday emotion (anxiety and depression) during the COVID-19 pandemic. The two categories of sex and the ages of social media users did not significantly moderate the relationship between social media use and everyday emotions, contrary to other studies ,51. It iFinally, actual reported levels of anxiety and depression associated with social media use among international students in COVID-19 were generally not severe. Users reported predominantly mild levels of stress assessed with GAD-7 and depression assessed with PHQ-9, as shown in This study found social media use during the COVID-19 pandemic to positively impact international students’ everyday emotions. This finding contradicts other studies that have found excessive use of social media to negatively impact users’ behaviors, especially among young people and “mobile-borns.” The study emphasized the immerse use of social media among international students to curb the adverse effect of everyday emotions, which seems to be a significant mental health threat among students. Based on the findings of this current study, it is suggested that stakeholders continue to implement programs such as online mental health consultations, counseling programs, and public health education campaigns for maintaining social support and enhancing public trust in public health measures. The continuation of these programs will help consolidate the gains made in pre-empting and eliminating anxiety and depression associated with social media use among international students. Furthermore, it is also imperative for international students to avail themselves to access these existing programs and other ones that stakeholders roll out in the future to safeguard their holistic well-being in COVID-19. Finally, to the best of our knowledge, this is the first study on international students’ everyday emotions and social media use in the era of the COVID-19 pandemic. We also believe that these results are highly representative of, and generalizable to, the population of international students in China, owing to the standardized procedures of data collection and findings established.This study had three main limitations which could be addressed in future research. First, the study focused solely on the impact of social media use on international students’ everyday emotions during the pandemic. However, understanding the influence of social media use on everyday emotion in non-pandemic situations will be extremely useful. Such studies will help determine whether there are differences in the magnitude of the impact of social media use on everyday emotion in the two situations. Second, this study could not ascertain whether or not the relationship between social media use and everyday life among international students and Chinese students is similar. Future research should compare a sample of international students with a similar sample of Chinese students to see whether there are any parallels in the influence of social media use on everyday emotion between these two groups. Lastly, “mobile-borns” are perceived to be at a high risk of addiction due to their excessive exposure to social media in the pre-pandemic period. This exposure may have enabled them to develop defense mechanisms to cope with social media-related anxiety and depression in the pandemic. However, this current study did not explore this dynamic. Thus, future studies may consider exploring this dynamic further.


The provision of public adaptive coping strategies to reduce psychological tension during the ongoing COVID-19 pandemic is critical. We sought to provide evidence-based guidance for psychological intervention, exploring the potential mediating roles of three sources of social support  between coping strategies , and anxiety among college students at the height of the pandemic in China.Using the Coping Strategy Questionnaire, Social Support Questionnaire, and Self-Rating Anxiety Scale, this large-scale online study analyzed the levels of social support, coping, and anxiety among 2640 college students in China from February 21st to 24th, 2020, when the students had been isolated at home for 1 month since the lockdown of Wuhan city.Students reported high levels of cognitive coping, behavioral coping, and social support. They also experienced low levels of anxiety and emotional coping. Anxiety was significantly and negatively related to coping and social support. The mediating roles of three sources of social support were found between cognitive coping, behavioral coping, and anxiety, respectively. However, the effect of emotional coping on anxiety was not found to be mediated by social support.Adopting positive coping strategies may enhance social support that in turn relieves anxiety. The effect of social support, especially family and counselor support, should arouse greater awareness in coping with the pandemic cognitively and behaviorally.The online version contains supplementary material available at 10.1186/s12889-021-11332-4. The outbreak of Coronavirus Disease 2019 (COVID-19) has invoked panic and anxiety in the world. Under this unprecedented circumstance, the Chinese government has taken an active stance and implemented extreme measures to mitigate the dissemination of the disease. Some of these measures include suspending all public emigration in Wuhan on January 23rd, 2020, introduction of forced quarantine for citizens in the peak period, extending holidays, and closing schools .In addition to coping strategies, a range of negative psychological consequences is usually accompanied by physical harm during the outbreak of a pandemic, such as depression, panic, and anxiety . A recenStewart’s coping theory stated that social support should be determined as one of the coping resources . Since sAlthough a variety of studies have drawn attention to coping strategies, anxiety, and social support , 13, fewRQ1: What is the status of coping strategies, social support, and anxiety among Chinese college students?RQ2: What are the relationships between coping strategies, social support, and anxiety?Using stratified random sampling in terms of students’ sex, major, and academic degree in this large-scale study, 2640 college students from a comprehensive university in Shenzhen, an important economic zone in China, completed the online survey during February 21st to 24th 2020, when the students had been isolated at home for at least 1 month since the lockdown of Wuhan city. The following research questions and hypotheses in the context of the COVID-19 pandemic are proposed.H1: The relationship between cognitive coping and anxiety is mediated by social support.H2: Social support has a mediating effect on the relationship between emotional coping and anxiety.H3: Social support plays a mediating role in the relationship between behavioral coping and anxiety.Given the mediating role of social support between performance and mental health, is it plausible that various sources of social support mediate the relationship between coping and anxiety during the pandemic? Based on the findings above, three hypotheses are proposed.The conceptual model is presented as follows Fig. :Fig. 1NCoping strategies are widely classified as either positive or negative . HoweverTo address pandemic coping more specifically, the present study adopted Lazarus and Folkman’s theory of psychological stress which divided coping into problem-focused coping  and emotion-focused coping confronted with stress , and claIn the social support norm, subjective support denoted individual resilience targeting the stressors in the pandemic, which comprises personal competence and confidence in one’s instincts to cope with adverse circumstances . Family The SCQ was designed to collect students’ sociodemographic data, including sex, major, academic attainment (graduate or undergraduate), current location , isolation condition , and self-perceived health status.The CSQ was used to evaluate coping strategies adopted by the students in the COVID-19 pandemic. This novel questionnaire was framed on the theory of psychological stress , and COVPrincipal components analyses were conducted to verify the validity of this scale. The Kaiser-Meyer-Olkin test yielded an index of 0.795, and Bartlett’s test of sphericity was significant. Three factors emerged, accounting for a total of 61.396% of the variance, with the factor of CC, EC, and BC accounting for 24.540, 18.674, and 18.183%, respectively. The Cronbach’s alpha coefficient was 0.83 with 0.70, 0.67, and 0.77 for each subscale dimension  respectively.The SSQ revised from the Chinese version of the SSQ was used to assess the levels of social support perceived by the students . The queThe anxiety of the students was measured using the SAS . The SASThis study was granted ethics approval by the Human Research Ethics Committee of City University of Macau (EA2001025). Eligible participants were young adults aged 18 to 25 years who are currently enrolling at a Chinese university. Of the 2680 participants recruited, 2640 students completed the survey, for a return rate of 98.5%. Subsequently, the data of 2640 participants were validly analyzed in this study. The participants were sent an email with the purpose and requirements for the investigation. After granting permission for inclusion, the respondents completed the questionnaires during February 21st and 24th of 2020 anonymously via an online survey with a random gift card distribution as incentives at the end of the questionnaires.The data were analyzed using IBM SPSS statistics 24.0 for Windows . First, descriptive statistics were used to summarize the demographic characteristics of the participants and the means of the investigated variables. To test the normality of data distribution, one-sample Kolmogorov-Smirnov test and histogram plot were used. Then, correlations between coping, social support, and anxiety were measured by Spearman’s correlation analyses. Finally, to explore the roles of social support in mediating the relationships between coping and anxiety, bootstrapping was applied with 5000 resamples with bias-corrected 95% confidence intervals (CI). In the mediation effect test, if the 95% CI did not contain zero, the mediation effect would be significant at the 0.05 level . MeanwhiDemographic characteristics are presented in Table p = 0.000) [The means and standard deviations of coping, social support, and anxiety are given in Table = 0.000) .Table 2r = −.211, p < 0.01), and social support . More precisely, the correlation coefficient between anxiety and social support  was distinctly higher than that between anxiety and behavioral coping . Notably, emotional coping was not significantly correlated with social support .Confirmed as abnormally distributed data, Spearman’s correlation analyses were conducted. The results in Table p > 0.05). The differences between male and female appeared insignificant in social support and the subscales of social support (p > 0.05), but significant in anxiety . However, G*Power analyses showed that the effect size index d (Cohen’s d = 0.183) was smaller than 0.20, which indicated that the significant difference of sex in anxiety addressed little effect size [After finding internal links among coping strategy, social support, and anxiety, the study examined the potential mediating role of social support between coping strategy and anxiety. To obtain a detailed insight into coping strategy, the effect of the mediator variables was explored between the subscales of coping strategy  and anxiety by bootstrapping. Since sex and academic attainment may serve as covariates, independent sample t-tests were used to compare group differences in the social support (M variable) and anxiety (Y variable). T-tests analyses showed that there were no significant differences in social support, the subscales of social support, and anxiety among students with various academic attainment (ect size . Therefop = 0.001). After the addition of social support, the indirect effect in the social support and anxiety pathway was negative and significant , indicating that social support strengthened the negative effect of coping on anxiety. Furthermore, it is worth noting that subjective support positively and significantly affected anxiety . The path through the mediation of subjective support , family support , and counselor support  were statistically significant, which supported H1.The mediating role of social support between cognitive coping and anxiety was evaluated first see Fig. . In the The mediating role of social support between behavioral coping and anxiety was then tested. As shown in Fig. However, the mediation analysis of social support between emotional coping and anxiety indicates that the path through the mediation of subjective support , family support , and counselor support  were all statistically insignificant, which did not support H2.This study was conducted on a sample of Chinese college students to investigate the relationship between coping, social support, and anxiety during the COVID-19 pandemic. Two research questions and three hypotheses were proposed. The levels of Chinese college students’ coping strategies, social support, and anxiety were described, and a model of the relationship between coping strategies, social support, and anxiety was developed. Accordingly, some meaningful findings and implications were also drawn as follows.First, this study found that the levels of cognitive coping, behavioral coping, and social support for Chinese college students were high while those of emotional coping were considerably lower. The finding of high cognitive coping is consistent with the finding that more than 90% of the Chinese public kept updating pandemic information . HoweverFurthermore, the mean anxiety scores of the students were found to be higher than the Chinese norm of the SAS in the usual time, but much lower than those self-isolated in central China during the epidemic . SimilarSecond, Spearman’s correlation analyses found that anxiety was significantly and negatively related to coping and social support and that social support possessed the greatest links with anxiety among these associations. This verified the dominating role of social support in buffering anxiety, which left room for further mediation analysis. There was a mediating effect of social support on the relationship between cognitive coping, behavioral coping, and anxiety, while social support did not mediate emotional coping and anxiety. Moreover, the path through family support and counselor support had stronger mediating power than subjective support. The influence of cognitive coping and behavioral coping on anxiety was mediated by social support, supporting H1 and H3. In the first path, cognitive and behavioral coping positively affected social support. Individuals with a sufficient input of information may be fully aware of the current epidemic situation, delivering an encouraging emotion to their family or themselves . The conOverall, the finding of the positive mediating effect of social support is of great value because it provides empirical evidence to emphasize the implementation of social support. Therefore, it is urgent to take measures to facilitate social support during the COVID-19 pandemic. For instance, regarding the information about infectious diseases, individuals should avail themselves of the suggestions of professional medical staff . Second,However, there are some limitations to the current study. First, the samples were restricted to one university, which may be less generalizable to the entire population. Second, the cross-sectional design of this study could not reflect the long-term development of the samples, which needed supplementary findings from longitudinal research. In addition, all the questionnaires were self-reported, and the veracity of the result relied on the self-perception of the subjective and non-subjective methods should be applied. Last but not least, anxiety as a dependent variable involved in the survey could not reflect an intact picture of mental health, and it is necessary to further explore other factors indicating traumatization, such as depression, fear, despair, and irritability.The findings in this empirical study are supposed to present a clue in psychological interventions and behavioral guidance on the current global crisis. First, this study detected high levels of cognitive coping, behavioral coping, and social support, explored low levels of anxiety and emotional coping for Chinese college students at the peak of the COVID-19 pandemic from January to February 2020. Second, anxiety was negatively associated with coping and social support. Third, social support played as a mediator in the relationships between cognitive coping, behavioral coping, and anxiety, with family support and counselor support exerting a stronger negative power against anxiety than subjective support.In view of the implications proposed, there appear to be alternate strategies to ease anxiety. These findings may provide evidence for promoting social support, especially family support and counselor support, as facilitating sources to decrease anxiety in coping with the COVID-19 pandemic cognitively and behaviorally. Policymakers and school administrators should encourage meaningful communication between family members and activate effective counseling services to maintain positive mental health.Additional file 1: Table S1. Items of Coping Strategy Questionnaire (CSQ).


N = 18 bilingual adult speakers of German  with different ages of onset participated in this study and were compared to N = 26 monolingual German adult speakers (mean age 23.9). All participants had a proficiency of German above 89% correct in placement and cloze tests. Results show fully comparable productive and comprehensive competencies in monolinguals and bilinguals including the reaction times in the sentence-picture matching task and a word order effect on the reaction times in both groups. In the pupillometry task, we found monolinguals and bilinguals to be sensitive to differing conditions with respect to grammatical and ungrammatical utterances. However, we find between group differences in pupil dilations in that bilinguals react differently to strong grammatical violations than monolinguals. These results are discussed with respect to the term of native speaker competence and the variation within both groups.The present pilot study investigated potential effects of early and late child bilingualism in highly proficient adult bilinguals. It has been shown that some early second language (eL2) speakers stagnate when it comes to complex linguistic phenomena and that they display subtle difficulties in adulthood. Therefore, we have chosen the complex structure of double object constructions. We investigate the long-term achievement in a combined-method approach using elicited production, explicit comprehension by sentence-picture matching and a measure of implicit linguistic knowledge, namely pupillometry. This eye tracking method is suitable for measuring implicit reactions of the pupils to unexpected or ungrammatical stimuli. For production, ditransitive structures were elicited by means of a game. For comprehension, a sentence-picture matching task was conducted. Two pictures were shown on a monitor that were equal with respect to the involved objects, but the thematic roles of direct and indirect objects were interchanged. Items were controlled for length, gender, animacy, semantic likelihood and word order. Reaction times and accuracy scores were analyzed. To this end,  In research on bilingual language acquisition and its outcome in adulthood, it has been shown that some of the children acquiring an early second language (eL2) are doing well on this acquisition task and others struggle with more complex structures at some point in their acquisition process and stagnate or fossilize Paradis, . ParadisIn the present pilot study, we investigated in depth highly proficient bilingual adults with various ages of onset instead of focusing on moderating factors of the ability to become highly proficient in a second language (L2). For this purpose, we performed a study with respect to the different modalities of production and comprehension and implicit grammaticality judgements, regarding ditransitive structures, a complex morphosyntactic phenomenon. Our aim was to evaluate possible subtle differences between bilingual and monolingual speakers, as Paradis  postulatsomeone who is able to predict what the other person is going to say, therefore enabling a native speaker to anticipate upcoming input. Others suggested to characterize native speakers by their competence to identify ungrammatical utterances and thus to provide valid grammaticality judgements on their language using intuitive knowledge of the grammatical sentence  attainment”  or zeigen (to show), that select a nominative subject (SUBJ), a direct object (DO) typically marked for accusative (ACC) and an indirect object (IO) typically marked for dative (DAT). Three thematic roles are assigned  and eL2 acquisition literature, there is consensus that, owing to its high complexity, German case marking is acquired very late compared to other acquisition phenomena . Here, the production of the IO die schnecke is assumed to be an overgeneralization of the accusative. Before achieving target-like utterances like in Example 1, L1 children show an extended period of difficulties with these structures , whereas seven-year-old children behaved like adults by relying on case markers rather than word order . In line with these results, Brandt et al.  report iIn an experiment using the same methods as the present study, Scherger et al. (submitted)move. The same anticipation mechanism was found with respect to the morphosyntactic cue of case marking. Adult native speakers of German anticipated the second nominal phrase (NP) of a sentence on hearing the case-marked first NP  than to grammatical utterances .With respect to VoE, pupillometry has been shown to be a useful marker for the ability of 30 months-old toddlers to differentiate between correct and incorrect pronunciations ,comprehend ditransitive structures accurately (comprehension),use the case marking cue of the first object for anticipating the thematic role of the second object (predictive processing) andreact implicitly to ungrammatical auditory stimuli by a change in pupil size ?Considering prior findings, we assume that the participating L1 and 2L1 speakers can produce and understand the tested ditransitives. Therefore, we expect performance at ceiling in the production and comprehension tasks. However, we expect subtle difficulties in eL2 and late L2 learners of German regarding production of the dative case marking, because prolonged difficulties in children have been shown in Lemmer  and ScheN = 26) and bilingual (N = 18) participants were matched based on age . All participants were university students and received course credits for their participation in the experiments.In this study, 44 adult speakers participated see . MonolinN = 6, AOO = 0;0; eL2: N = 7, AOO = 3;0–4;0; late L2 learners: N = 5, AOO = 6;0–13;0). Various L1s were included in the bilingual group: Albanian (N = 2), Arabic (N = 1), English (N = 1), Italian (N = 1), Kurdish (N = 1), Polish (N = 4), Russian (N = 2), Serbian (N = 1), Spanish (N = 3), Turkish (N = 1), and Vietnamese (N = 1). Participants were assigned to the corresponding groups according to our definition of mono- or bilingualism based on self-reports.Monolingualism was defined as having acquired only one language  in the first years of life. This does of course not exclude the learning of an L2 at school. In the bilingual group, simultaneous and sequential bilinguals were included on purpose so that different AOOs could be compared . Overall, the game consisted of 27 cards with pictures of animals. The participants had to give/donate the animals on the picture cards to one recipient  describing their action. This resulted in utterances like ich gebe das pferd dem schaf or ich gebe dem schaf das pferd . These two verbs are comparable with respect to their semantics, lengths, and subcategorization frames. Both are frequent and attested to be acquired early in German . Moreover, utterances were analyzed separately with respect to the word order produced: DO-IO (see Example 6a) or IO-DO (see Example 6b). N = 462 and in monolinguals was N = 644 .The amount of analyzed utterances in bilinguals was SD = 1.0) and 1.8% (SD = 0.8) of all the produced objects were built with pronouns by bilinguals and monolinguals, respectively. These occurrences were excluded from the analysis for a better match within the comparison of comprehension and production data. Furthermore, we excluded realizations of indirect objects by prepositional phrases (PPs), since this structure does not mandatorily require a dative case marking (see Example 7). Utterance dropout rates because of producing PPs were 3.3% (15/462) in bilinguals and 2.6% (17/644) in monolinguals. These numbers confirm results reported by Kholodova and Allen  were excluded from the analysis since they may select different subject and object structures with different case assignments . Moreover, utterances including verbs other than Participant as a random intercept. Then, models were compared using the Akaike Information Criterion  with a logit link function, assuming a binomial error distribution for the binary response (correct/incorrect production). For the analysis, we used lme4 package , from birth as 2L1, early L2 onset, late L2 onset,participants based on the L1 case systems similar or different to German: same , similar, different,Group as a fixed-effects factor, plus random-effects factor Participant as random intercept.we compared three GLMMs including different versions of When categorizing the languages, we focused solely on marking of objects in the form of common nouns. Pronominal forms were not considered as only the use of full DPs (with definite articles) was relevant in this production task as well as in the following experiments (study 2 and study 3). We categorized a language as similar to the German case system when a case system with different cases used for subjects and objects as well as for the two objects of ditransitive structures was present. The categorization of case systems' similarity was specifically based on the presence of dative structures like in the German case system. All case systems of the languages categorized as similar, namely Albanian, Polish, Russian, Serbian and Turkish, have five to seven grammatical cases, among which are the accusative and the dative case. In Arabic, there are three grammatical cases. However, unlike in German, only the accusative is used for the object of a verb and it can mark both objects in double object constructions Mohamed, . TherefoGroup and WordOrder had an influence on production accuracy, we ran separate GLMMs for produced accusative and dative objects.To evaluate the question whether Group. The GLMM performing best was the one where bilinguals were further split according to AOO , but the differences between models were rather small. We continued with Group as split by AOO.As described under 3.2, we first evaluated the different ways to model Group as defined above and WordOrder {IO-DO, DO-IO} on accuracy of the accusative object. To this end, we set up a model space as reported in Participant was highly significant , p < 0.001].Second, we tested the influence of Group, that is, AOO, nor WordOrder helped explaining the variance in the data. The data were best explained by inter-individual variation only. This finding is not surprising given that monolinguals and bilinguals showed ceiling performance.In other words, neither The few occurrences of errors in production within the bilingual group see  were conGroup. The comparison of the monolingual/bilingual vs. AOO vs. case marking system of L1 models revealed that again AOO was the slightly better estimate (AICs = 95.79 vs. 95.64 vs. 95.77). Thus, we continued with Group as AOO.Again, we first evaluated how to best model the factor Group as defined above and WordOrder {IO-DO, DO-IO} on accuracy of the dative object with the same models as for the accusative  were simultaneously presented to the participants at a distance of 100 pixels in the middle of the screen on a gray background see . Particider for dative feminine singular and nominative masculine singular; since the latter is the default, the dative feminine der could be biased. We further excluded masculine items because of the difficulty to discriminate accusative and dative forms of den and dem. Therefore, all the objects included in the sentence-picture matching task were of neuter gender . In addition, we added a task-irrelevant adverb between the indirect and direct object to provide time to parse the first object and react before hearing the second object. Example 10 illustrates the item composition. Regarding the stimuli of the comprehension task, we controlled for animacy, definiteness and verb bias as was described above for the production task. We only included objects that were [+animate], definite and consisted of full lexical DPs. To control for auditory length in addition, we restrained the maximal word length of objects to two syllables . The subjects were kept consistent in 1st person singular for test trials. Regarding grammatical gender, we excluded the feminine gender from the comprehension task because of the homonym form of die giraffe frisst auf der wiese [the giraffe eats in the meadow] vs. das schaf frisst auf der wiese [the sheep eats in the meadow], see item list in www.random.org). After that, we manually adapted the resulting random order because of task-related issues. When a test trial followed immediately after a break, we changed the order and put a filler item instead . These labels are created by pressing their respective hotkey . Regarding the RT analysis, we defined critical windows to investigate how fast participants would react after hearing the first case marking see . RTs wermin = 1,471 ms, max = 1,999 ms). Therefore, prediction ratings were scored individually for each item.Regarding predictions, we followed Schlenter , p. 2 inParticipant as a random intercept. Models were compared using the AIC. For the purpose of model comparisons, Maximum Likelihood estimation method was used. The statistics of the winning model (= lowest AIC) are reported in full in the text.Data were analyzed using linear mixed-effects models (LMMs), assuming a Gaussian distribution for interval-scaled RTs and GLMMs with a logit link function for binary accuracy with lme4 package , from birth as 2L1, early L2 onset, late L2 onset,participants based on the L1 case systems similar or different to German: same , similar, different,Group as a fixed-effects factor, plus random-effects factor Participant as random intercept. The results were clear: The differences were negligible (AICs: 1534.87 vs. 1534.88 vs. 1534.90). We decided to continue with version (a) of factor Group, because of its lowest AIC.we again first compared three GLMMs including different versions of Group {monolingual, bilingual} and WordOrder {IO-DO, DO-IO}, we set up different models as described in Then, to evaluate the different influences of Participant , z = 9.27, p < 0.001].Thus, regarding the accuracy in the sentence-picture matching task, we did not find any differences aside from the ones that were due to inter-individual differences based on random-effects factor Group as a fixed-effects factor, plus random-effects factor Participant as random intercept. The comparison of the monolingual/bilingual vs. AOO vs. case marking system of L1 models revealed that AOO was the slightly better estimate (AICs: 1437.41 vs. 1437.37 vs. 1437.40). Again, the differences in AICs are marginal. Nevertheless, we continued by modeling Group as AOO.Reaction times were similar in monolinguals and bilinguals see . For theGroup {monolingual, bilingual} and WordOrder {IO-DO, DO-IO}, we set up different models as described in Participant was significant , t(47.99) = 20.117, p < 0.001] and fixed-effects factor WordOrder was highly significant , t(808.19) = −2.78, p = 0.006].Then, to evaluate the different influences of Mean RT for IO-DO  was smaller than for DO-IO , displaying a typical word-order effect.Group and WordOrder on whether participants were able to anticipate the upcoming second object. Only correct responses were analyzed. First, we assessed how to best model Group by comparing the three different assessments as before. Again, all model fit estimates (AICs) were relatively similar . As the simple differentiation only based on mono- vs. bilingual was the best fit, we used this for Group.Regarding anticipatory reactions, we evaluated the influence of WordOrder and Group had explanatory value for anticipation. The full model space is provided in Participant was not significant , p = 0.302].We then assessed which GLMM fit the data best with regard to whether Group nor WordOrder appear to influence the number of anticipated second objects.Thus, neither In accordance with this, Lastly, there were no significant correlations between any of the tested WM categories and overall rate of anticipatory reactions see .Pupil Core, Pupil Labs). We used a 9-point eye tracker calibration before the pupillometry task started. To avoid confounding implicit pupil measurements with a participant's explicit action, i.e., manual response, the participant's task was simply to listen to the auditory stimulus. To minimize reflexive reactions of the pupil diameter to changes in luminance, we kept the displayed colors constant. Therefore, the monitor displayed a black fixation cross on a gray background while auditory stimuli were played. After a block of five trials, there was either a comprehension question to check for the participants' attention  or pause with a picture of a forest to relax the eyes. The only explicit reaction that was required by the participants throughout the experiment was to press a button (yes/no) to answer these comprehension questions. Throughout the presentation of the forest picture, the participants were told to do whatever they like to relax the eyes . The stimuli following the comprehension questions and the stimuli following the relax pictures were fillers that were not analyzed.Pupil data were tracked by a Pupil Labs eye tracker at 200 Hz  pupil dilation. All models were estimated using Maximum Likelihood estimation.To find the best model fitting the data, we set up a model space including different combinations of fixed-effects factors and random smooths as elaborated below. The full model space is provided in Participant over Time s {time, participant} to model the variance of the pupil response over time that is only due to inter-individual differences. We chose to also estimate a second null model M0, which also included a random smooth s {time, trial}to account for trial-wise variation over time. Because M0 was the better null model, we included both random smooths in all models of interest , because the measured pupil dilation is confounded with it. Depending on the angle, the pupil appears oval instead of round, leading to an underestimation of the pupil size. The null model M00 further includes a random smooth for t M1–M3, .Violation {A, B, C}, Group {monolingual, bilingual}, or both VioGr {A-monolingual, A-bilingual, B-monolingual, B-bilingual, C-monolingual, C-bilingual}. Due to the nature of GAMMs, an interaction term cannot be included as one would do for LMMs. Thus, we included a factor VioGr combining all levels of Violation and Group. The best fitting model by far was M3, the one including the factor VioGr.Models M1–M3 further included either a fixed-effects factor to model main effect of Participant and Trial, pupil dilation varied as a function of Violation {A, B, C} and Group {monolingual, bilingual}. This is depicted in In this task the pupil dilation is expected to change with violation (condition B and C vs. condition A). As to be expected from the winning model M3, excluding random effects of As This paper aimed to investigate monolingual and bilingual adult speakers of German with respect to their linguistic performance regarding production, comprehension, and implicit sensitivity to grammatical violations of the morphosyntactic complex double-object construction with ditransitive verbs. Therefore, we developed three experiments in which we elicited ditransitive structures (study 1), assessed accuracy and RTs in a sentence-picture matching task (study 2), and investigated sensitivity to grammatical violations via pupillometry (study 3).WordOrder had a descriptive, but non-significant influence on the production of the dative it would be interesting to see, whether the effect might reach significance, when performance is not at ceiling.In comprehension and production, bilinguals exhibited abilities that were comparable to monolinguals' in all aspects. Regardless of the AOO , all bilinguals performed at ceiling in production and comprehension tasks. The reported overgeneralisations of accusative in dative contexts in production were negligible and can be interpreted as performance errors. However, since The ability to anticipate upcoming input, i.e., using the case marking of the first object (dative marking in default word order and accusative marking in marked word order) to anticipate the upcoming input in bilinguals was comparable to that in monolingual speakers. This is in accordance with Schlenter's  findingsAs can be seen in the huge variability in monolingual and bilingual adults regarding anticipated reactions, the methodological set-up of this study limits definite conclusions about the underlying predictive ability. Nevertheless, the data show comparable levels of anticipated reactions for mono- and bilinguals, supporting the overall impression of bilinguals' native speaker competence. This is in line with Halliday's  definitiThe analysis of the participants' pupil data revealed a clear difference between the implicit response to grammatical (condition A) compared to slightly ungrammatical (condition B) and strongly ungrammatical sentences (condition C) in both, monolinguals and bilinguals. Taking, for instance, Chomsky's relation between native speaker and a grammatical sentence as a basis, the participants investigated here can be claimed highly competent since they were able to identify ungrammatical utterances implicitly and thus provide valid implicit grammaticality judgements on their language on the basis of intuitive knowledge of the grammatical sentence Chomsky, .Violation {A, B, C} but also as a function of Group {monolingual, bilingual}. The main difference between monolinguals and bilinguals in the timing of pupil reactions concerns the difference between A and C, i.e., the grammatical condition and the strongly ungrammatical condition. Here, monolinguals react faster to the grammatical violation than bilinguals, demonstrated by the differences between A and C that become significant earlier in monolinguals than in bilinguals. The bilinguals' delayed response when compared to monolinguals could be due to higher processing efforts. This interpretation would be in line with Fernandez L1 and AOO, evident in their comparable ceiling performance in production and comprehension, as well as their high sensitivity to grammatical violations in German utterances. We therefore conclude that at this proficiency level, AOO and cross-linguistic influence may not affect production and comprehension abilities in bilingual adult speakers of German. The documented high proficiency in all domains is in line with Hartshorne et al. , who proIn line with psycholinguistic research on early bilingualism, we included a control group of monolingual speakers in the present study. Our aim was to challenge the idealized monolingual L1 competence as the native speaker norm and evaluate the validity of this assumption. Our findings provide evidence for a new perspective on the term “native speaker.” Here, our data revealed that even so-called near-native speakers with AOOs later than 6 years could show high proficiency throughout. Characteristics previously attributed to native speakers . On the other hand, acquiring an additional language or being raised bilingually does not mean that someone is not able to achieve high competence, also in subtle and implicit measures. We therefore call for a different perspective on someone's language competence other than to tie it invariably to the place of birth and upbringing and the amount of languages that have been acquired.To this end, the two “groups”  that we compared and contrasted in our study can be collapsed in to one group: In fact, we see one group of highly proficient speakers of German with high performances on different explicit and implicit tasks that concern complex morphosyntax. With the add-on of some speakers who are additionally able to speak another language, representing a personal advantage for these speakers.The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.Ethical review and approval was not required for the study on human participants in accordance with the local legislation and institutional requirements. The patients/participants provided their written informed consent to participate in this study.A-LS developed the research ideas, the design of the study, and wrote the first draft of the manuscript. A-LS collected the data, with the help of JK. A-LS, JK, and TL performed the statistical analysis and created the visualizations. GU and JK wrote sections of the manuscript. All authors contributed to manuscript revision and approved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


Pain following orthopedic surgery has always been a critical issue, which caused great distress to the patients. Analgesics in the treatment of postoperative pain following orthopedic surgery have aroused great attention from scholars, and numerous studies have been published in recent years. Bibliometrics could assist scholars in understanding the scope of research topics better, identifying research focuses and key literature, and analyzing the development and trend of analgesics in the treatment of postoperative pain following orthopedic surgery.  Literature data were retrieved from the Science Citation Index Expanded (SCI-E) of Web of Science (WOS) Core collection database. The articles from 1992 to December 2021 on analgesics in the treatment of postoperative pain following orthopedic surgery were recruited. The citation reports including the publication numbers, h-index, total citations, and average citations in terms of authors, organizations, and countries were obtained. Top 20 research directions, funds, and journals with the most publications were charted. The co-authorship relations in the analysis units of authors, organizations, and countries were analyzed by the online bibliometric tool and VOSviewer software. The author's keywords co-occurrence overlay map was visualized by the VOSviewer software. n = 887), Ilfeld BM from University of California San Diego (n = 7), University of California System (n = 21), the USA (n = 178), Anesthesiology (n = 161), National Institutes of Health (NIH), USA, and United States Department of Health Human Services (n = 12), and Anesthesia and Analgesia (n = 29), respectively. Similarly, co-authoring analysis of publications regarding on different analgesics showed that the authors and countries with the most co-authorship strength were Carr Daniel B  and the USA , respectively. The highest occurrence keywords were “postoperative pain” with 135 occurrences . The future research hotspots might be “acute pain,” “outcomes,” “oxycodone,” “total hip,” “replacement,” and “United States.”  A total of 406 articles were retrieved from 1992 to December 4th, 2021, with 11,655 times cited, average citations of 28.57 per item, and an h-index of 55. The most high-yield publication year, authors, organizations, countries, research directions, funds, and journals were 2020 ( Analgesics in the treatment of postoperative pain following orthopedic surgery can be observed in this study by employing the online bibliometric tool and VOSviewer software, which established the relationship between the units of analysis. It can provide a meaningful resource with detailed information for orthopedic surgeons who would like to understand the trend in this field better. They can also benefit from the emphasis on citation count to carry out high-level research in the future. Postoperative pain has always been a problem plaguing clinical treatment. In addition to the pain of the incision, many other factors can also cause pain, especially following the orthopedic operations, such as periosteal irritation, swelling of the affected limb, increased bone fascia tension, postoperative compression bandaging, and external fixation . More imThere are more than 53 million records and 1.18 billion cited references in the Science Citation Index Expanded (SCI-E) of Web of Science (WOS) Core collection database, which is an important resource for scientific statistics and evaluation . A bibliHowever, no bibliometric research on different analgesics in the treatment of postoperative pain following orthopedic surgery has been performed. This study aims to outline the intellectual connections within the dynamic changing of scientific knowledge in orthopedic postoperative analgesia using the WOS Core Collection database and the VOSviewer software.The literature data were retrieved through SCI-E of WOS Core Collection database, which is widely applied in bibliometric research using an advanced search strategy. The search query was “) AND TS = (Postoperative OR Postoperative Periods)) AND TS = ) AND TS = ) AND LA = (English) AND DT = (Article).” Timespan = all years. All articles were evaluated by two independent reviewers in order to confirm their relevance. Full records of all articles were searched on December 4th, 2021.https://bibliometric.com/) and VOSviewer 1.6.11 software . The author's keywords co-occurrence overlay map was implemented by VOSviewer, setting the minimum occurrences of a keyword to 5 times.The trends of publications and citations were charted annually. The distribution of the bibliographic records per year in different countries was also obtained. The top 20 most cited articles were recorded and analyzed by the following information: first author, article title, journals of publication, year of publication, total number of citations, and average citations. The records, h-index, total citations, and average citations in terms of authors, organizations, and countries were tabulated directly. The top 20 research directions, funds, and journals with the most publications were charted. The co-authorship relations in the analysis units of authors, organizations, and countries were mapped by the online bibliometric tool (n = 29) was 2020. The citation started in 1992, and the year with the most times cited was 2020 (n = 887). The results showed a fluctuating increase year by year.A total of 406 articles were retrieved in the SCI-E of WOS Core Collection database from 1992 to December 4th, 2021, with 11,655 times cited, average citations of 28.57 per item, and an h-index of 55. The USA had contributed 178 articles (43.842%) at the top. Canada was the second contributing country with 25 articles (6.157%), followed by England with 22 articles (5.419%) and France and Germany both with 20 articles (4.926%). China only ranked 9th with 13 articles (3.186%). Only two countries contributed articles in 1992. However, more and more countries published articles yearly, and the number of involved countries increased to ten in 2021. The USA dominates in this field almost every year. The distribution of the bibliographic records each year of the top 10 countries on analgesics in the treatment of postoperative pain following orthopedic surgery is shown in This search collected a total of 406 articles between 1992 and 2021 from WOS. The top 20 most cited articles are given in There were 1,961 authors, 745 organizations, and 46 countries contributing to this field. There were 37 research directions, 154 funds, and 174 journals contributing to this topic. The authors with the most co-authorship strength were Carr Daniel B, Daniels et al. , ViscusiThe overlay visualization of the top 162 co-occurrence keywords is shown in Bibliometrics mainly collects bibliographic databases and bibliometric features and uses mathematical and statistical methods to qualitatively and quantitatively analyze the relevant information of the literature, such as the distribution of countries, authors, journals, institutions, and funds. It also helps researchers grasp the development trend of this field intuitively and quickly , 22. UsiThe popularity of a specific topic can be reflected by the number of publications. The study on analgesics in the treatment of postoperative pain following orthopedic surgery was initially published in 1992. The number of articles published fluctuated around ten from 1992 to 2007 and increased significantly from 2008 to 2021. Meanwhile, the quality of a specific topic can be judged by the number of citations . There wAs shown in Citation analysis is a systematic method to evaluate the influence of scientific research . An artiThe second most cited article was a retrospective review by Chung et al. in 1997 in Anesthesia and Analgesia , focusinThe latest literature was a randomized controlled trial by Marino et al. in 2009 in Journal of Bone and Joint Surgery, paying attention to continuous lumbar plexus block for postoperative pain control after total hip arthroplasty. The conclusion was that continuous lumbar plexus and femoral blocks significantly reduce the need for opioids and decrease related side effects . Anotherh articles in the literature that have been cited at least h times by other scholars, which is a measure to evaluate an author or country by the number of academic output and the index of the academic output level [H-index refers to ut level , 30. Theut level .Among the top five high-yield authors, three come from the USA, Ilfeld BM from University of California San Diego, Carr DB from Tufts University, and Liu SS from Virginia Mason Medical Center. Similarly, four were in the USA among the top five high-yield organizations, including University of California System, Pennsylvania Commonwealth System of Higher Education Pcshe, University of Pennsylvania, and Cleveland Clinic Foundation. This may explain why the USA was ranked at the top one with a total of 178 records, which is far more than that in other countries .As shown in Figures 3In addition, National Institutes of Health (NIH), USA, and United States Department of Health Human Services were the most high-yield funds. Both of them belong to the USA. This was a good reason to explain why the USA was dominant in this field.Identifying the dominant journals in a specific topic can help scholars construct scientific achievement. Anesthesia and Analgesia, Journal of Clinical Anesthesia, Anesthesiology, and British Journal of Anesthesia were the most high-yield journals. Paying more attention to high-yield journals can assist scholars in accessing the most authoritative knowledge framework and the orientation of manuscript submitting. The publishers of these journals belong to the USA, while the rest one is from the UK. Researchers may benefit from this important information and realize the deficiencies when high-level articles appear .VOSviewer was used for cooperation network analysis of authors, organizations, and countries . Carr DBAs shown in VOSviewer was also used to generate a keyword co-occurrence map . The higAs all we know, bibliometric analysis has been widely used to measure the impact of articles in recent years. However, there are still some limitations to this method. First and foremost, we only used the core collection of WOS to search literature, which is a single database. The more databases we use, the more information we can get and analyze. Other databases such as InCites and MEDLINE should be considered in the future. Second, the main language of WOS is English. Articles written in other languages are excluded, which means some relevant articles be omitted. Third, the citation number of each study is time-dependent. For different time points to search the articles, different citations may be obtained. However, the trend of citation number of each study is nearly the same.This study has several advantages despite the limitations mentioned. It is the first study using the bibliometric method to search and identify literature on analgesics in the treatment of postoperative pain following orthopedic surgery, which has attracted increasing attention in recent years. Most importantly, our study provides valuable information for orthopedic surgeons and researchers in this field.To conclude, we researched and analyzed the literature information regarding authors, organizations, countries, research directions, funds, and journals and analyzed the thematic development and future research hotspots. Our research observes the raising concern on analgesics in the treatment of orthopedic postoperative pain in recent years. Anesthesia and Analgesia, Journal of Clinical Anesthesia, Anesthesiology, and British Journal of Anesthesia are the most influential journals. The future research hotspots might be “acute pain,” “outcomes,” “oxycodone,” “total hip,” “replacement,” and “United States.”


Neuropathic pain has long been a very popular and productive field of clinical research. Neuropathic pain is difficult to cure radically because of its complicated etiology and uncertain pathogenesis. As pain worsens and persists, pain recovery techniques become more important, and medication alone is insufficient. No summary of bibliometric studies on neuropathic pain rehabilitation is yet available. The purpose of the present study is to analyze in a systematic manner the trends of neuropathic pain rehabilitation research over the period of 2000–2019.  Studies related to neuropathic pain rehabilitation and published between January 2000 and December 2019 were obtained from the Science Citation Index-Expanded of Web of Science. No restrictions on language, literature type, or species were established. CiteSpace V and Microsoft Excel were used to capture basic information and highlights in the field. P < 0.001). The United States showed absolute strength in terms of number of papers published, influence, and cooperation with other countries. Based on the subject categories of the Web of Science, “Rehabilitation” had the highest number of published papers (446), the highest number of citations , and the highest number of open-access papers (151); moreover, this category and “Clinical Neurology” had the same H-index . “Randomized Controlled Trials” revealed the largest cluster in the cocitation map of references. The latest burst keywords included “Exercise” (2014–2019), “Functional Recovery” (2015–2019), and “Questionnaire” (2015–2019).  Linear regression analysis showed that the number of publications on neuropathic pain rehabilitation significantly increased over time ( This study provides valuable information for neuropathic pain rehabilitation researchers seeking fresh viewpoints related to collaborators, cooperative institutions, and popular topics in this field. Some new research trends are also highlighted. Pain reported that the best estimate of the prevalence of pain with neuropathic characteristics in the population may be between 6.9 and 10% [Neuropathic pain is a very popular and productive field of clinical research. In 2008, the IASP Special Interest Group (NeuPSIG) updated its definition of neuropathic pain as pain caused by a lesion or disease of the somatosensory system. Neuropathic pain is a fairly common disorder. Indeed,  and 10% . Neuropa and 10% , 6. As p and 10% . Psychos and 10% . The reh and 10% .No summary of the existing research on neuropathic pain rehabilitation is yet available. Bibliometrics combines mathematics, statistics, and philology to conduct quantitative research and analysis on a certain interdisciplinary field. It is an important academic link to obtain quantifiable, reproducible, and objective data . In addiThis review analyzes the current publications and development trends of neuropathic pain rehabilitation from the perspective of bibliometrics. The main institutions, extent of international cooperation, current situation, and trends are analyzed, and keyword cluster and world map analyses are used to reveal the research hot spots and leading countries in this field. A detailed bibliometric analysis of neuropathic pain rehabilitation research may help clinicians quickly and accurately classify and understand this field and guide future research directions.We collected synonyms related to neuropathic pain and rehabilitation and used “Subject Terms” for retrieval. The screening and downloading of literature for analysis was conducted on November 21, 2020. Literature from the last two decades (years 2000–2019) was downloaded from the Science Citation Index Expanded (SCI-Expanded) database of WoS.Our search strategy was as follows: TS=  AND TS= .H-index, open-access papers, and essential science indicator (ESI) top papers were directly obtained data from WOS and used as bibliometric indicators for visual analysis. All of the relevant data and references were stored in text format for subsequent visualization analysis. Publication count refers to the quantitative contribution of an author or institution. The number of citations, which refers to the sum of citations of all items in a set, can indicate the average quality of published papers. The H-index, also known as the H-factor, was proposed by Hirsch. This index evaluates authors' academic achievements in a specific field [H-index of an author is 30, all papers published by the author have been cited at least 30 times in 30 papers. Higher H-index values indicate more influential and persuasive papers. Open-access papers refer to the number of publications whose peer-reviewed versions are available free of charge from a publisher's website or repository.All of the data in this paper were extracted independently by the author (Xuan Su). EndNote X8  and Microsoft Office Excel were used to extract the data to be downloaded from WoS. We strictly followed the established retrieval strategy, extracted the target literature collection, created the citation report, and then obtained the target data. Data on publication count, citation frequency (including self-citations), number of citations per year, number of citations in 2019, ic field , 23. ForPain, Lancet, and Brain, on neuropathic pain rehabilitation were included without restrictions on the type of article or language used. The types of literature mainly included articles, reviews, and proceedings. Both animal and clinical studies were included.In this study, papers published in a wide variety of periodicals, including P value of <0.05 was considered statistically significant.The data were imported into CiteSpace (5.3.R11) in plain text format for analysis. CiteSpace V and Microsoft Excel were used to capture basic information and notable points in the field. The characteristics of the field were then studied in terms of discipline terms and keywords, and the publishing model of papers was assessed in terms of the number of publications in each country and the journal publishers. The frequency and percentage of journal and annual publications in each country were calculated on the basis of year of publication. The variation trends of research hot spots were studied through citation frequencies, keywords, and timeline views. Finally, we analyzed the citation trends of the top 10 countries, top 10 journals, and top 10 research fields to explore publishing patterns. IBM SPSS Statistics 22.0  was used to calculate the number of changes and determine whether the data are statistically significant. Linear regression analysis was performed on the data using category as the dependent variable and year as the independent variable. For example, analyze the number of articles published each year. A A total of 1,518 papers conforming with the retrieval requirements were collected. Articles and reviews accounted for 94.1% of the total number of articles collected. The remaining literature types included non-article-type documents, including proceedings papers, editorial materials, meeting abstracts, book chapters, early-access articles, corrections, letters, and reprints.t = 16.795, P < 0.001), thereby indicating that medical researchers are gradually expanding the field of research on the rehabilitation of neuropathic pain.The annual publication volume generally increased with some fluctuations over the years . A statix3 + 0.4058x2 + 1.1086x + 21.981 (R2 = 0.9577), and the predicted number of papers to be published in 2020 was 158.From 2000 to 2019, 1,518 papers were published in the field of neuropathic pain rehabilitation . The number of publications published in 2020 was forecasted on the basis of the growth rate curve of the number of publications by using the formular growth rate = −0.0072H-index peaked from 2010 to 2014. The citations in 2019 and the number of open-access articles peaked from 2015 to 2019.Among the four 5-year periods established , the most cited period per paper  was 2000–2004 , likely H-index (71), and the greatest number of open-access articles (196).H-index (21), and the University of Pittsburgh had the highest number of open-access articles (15). Published papers in the field of neuropathic pain rehabilitation involved a total of 2,014 institutions. A total of 1,518 papers on neuropathic pain rehabilitation research were written by 6,180 authors. Among the top 10 cocited authors , FinneruReferences are an important component of high-quality papers that not only provides a strong argument for the author's findings but also expands the information chain and reflects the scientific value of research. In other words, references are an important index that reflects the scientific basis of a paper.Q value, is a commonly used method to evaluate the strength of the network community structure. In this study, the Q value was 0.8705. A Q value higher than 0.3 indicates that the community structure is significant. The largest cluster (#0) was “randomized controlled trials,” followed by “complex regional pain syndrome” (#1), “spinal cord injury” (#2), and “central sensitization” (#3). Despite the fairly wide availability of research on the mechanisms involved in central sensitization or neuroinflammation in patients with chronic low back pain or musculoskeletal pain, the treatment of these issues remains a challenging scientific problem [A timeline view of the literature cocitation analysis is shown in  problem –37. Expe problem .Neurorehabilitation and Neural Repair  and Journal of Rehabilitation Research and Development , respectively. Because of the diversity of categories, four journals remained in Q1, thereby indicating that the overall impact factor of published papers in this field is not high. However, some categories such as “rehabilitation” and “exercise science” could be found in Q1.Over the last 20 years (2000–2019), a total of 585 journals published papers related to neuropathic pain rehabilitation. Active journals are defined as journals with the greatest number of publications within a certain period. As shown in A dual-map overlay of journals is shown in Keywords are the core summary of a paper, which can be analyzed on the topic of the paper. Authors generally believe that the more frequently lexical pairs appear in the same literature, the closer the relationship between these two topics. The most common keywords were diabetes mellitus, neuropathic pain, low back pain, and spinal cord injury , citations , and open-access papers (151). “Anesthesiology” showed the highest number of citations per item (26.64), and Engineering Biomedical demonstrated the highest number of citations per paper (65.42). The H-index of Rehabilitation and Clinical Neurology was identical at 52.The 1,518 papers on neuropathic pain rehabilitation research were allocated to 87 topic categories in WoS. Among the top 20 subject categories , “RehabiP < 0.001) in the top 20 categories .Linear regression analysis showed that the percentages statistically increased over time , is effective in treating the disease , 40Spinal cord injury: chronic neuropathic pain after SCI is a complex disease, and transcranial direct current stimulation is effective in clinical treatment . The latCentral sensitization: central sensitization is a kind of hypersensitivity to pain caused by central neural plasticity, which is interwoven with psychoneuroimmunological interactions , 35, andAnalysis of the comorbidity map of the references showed that “randomized controlled trials” was the largest cluster, and the other large clusters are as follows:ExerciseAnalysis of the keywords with the strongest citation bursts from 2000 to 2019 revealed major hot spots in the field of neuropathic pain rehabilitation  Functional recoveryThe effect of sports on the improvement of lower back pain, diabetic neuralgia, and pediatric pain has also been affirmed by professionals –50. Exer(3) OutcomeNo evidence from randomized trials indicates that treatment is necessarily effective. For example, randomized clinical trials are needed to determine the efficacy of glucocorticoids or other immunoregulatory therapies in the treatment of neuralgia muscular atrophy . In one The efficacy of different interventions in the treatment of neuropathic pain could be evaluated by analyzing data on pain, function, dose, and adverse effects in randomized controlled trials. Knowledge of outcomes can help patients choose the appropriate rehabilitation treatment , 55.This article is the first to summarize the research current status, geographical distribution, research hot spots, and development trends in neuropathic pain rehabilitation worldwide. Our study encompasses 20 years of data extracted from WoS and analyzed by CiteSpace and, thus, provides strong evidence of the future development of research in this field through keywords and subject categories. The soft power of science and technology of each country was visualized using a world map of the distribution of published papers, institutions, journals, and countries. Analysis of the authors and cited authors could help identify leaders in this domain. However, the limitations of our work must be acknowledged. First, although we believe that WoS is a suitably large database that can provide a wide variety of publications critical to our analysis, future researchers could use other databases, such as Scopus, Embase, Ovid-Medline, and China Knowledge Resource Integrated (CNKI), to explore other potential papers. Future studies can broaden the search scope to include more relevant studies to enrich the literature. Finally, some keywords that did not provide much information, such as risk, model, and system, could not be analyzed.Our understanding of neuropathic pain rehabilitation has advanced remarkably over the last 20 years. Using bibliometric charts, we illustrated the overall structure of scientific research on neuropathic pain rehabilitation and provided comprehensive information related to this field for other investigators. The most recent burst keywords were “exercise,” “functional recovery,” “outcome,” and “questionnaire.” This analysis provides a comprehensive overview of relevant research conducted in the area of neuropathic pain rehabilitation.