Many factors affect road safety, but research constantly shows that drivers are the major cause of critical situations that could potentially lead to a traffic accident in road traffic. Visual information is a crucial part of input information into the driving process; therefore, distractions of overt visual attention can potentially have a large impact on driving safety. Modern eye tracking technology enables researchers to gain precise insight into the direction and movement of a driver’s gaze during various distractions. As this is an evolving and currently very relevant field of road safety research, the present paper sets out to analyse the current state of the research field and the most relevant publications that use eye tracking for research of distractions to a driver’s visual attention. With the use of scientometrics and a qualitative review of the 139 identified publications that fit the inclusion criteria, the results revealed a currently expanding research field. The narrow research field is interdisciplinary in its core, as evidenced by the dispersion of publication sources and research variables. The main research gaps identified were performing research in real conditions, including a wider array of distractions, a larger number of participants, and increasing interdisciplinarity of the field with more author cooperation outside of their primary co-authorship networks. Road accidents continue to be one of the major causes of deaths worldwide. In 2016, road injuries were the eighth top cause of deaths, killing 1.35 million people worldwide [Rupp  notes thVisual attention is therefore of key importance for successful and safe driving. As early as the 70s of the 20th century, researchers estimated that as many as 90% of the information needed for driving is obtained through the visual channel . AdditioResearch on distractions affecting the driver while driving is likely as old as the act of driving itself. The first researches of advertising boards, one of the most researched influences on visual attention drivers even today, appeared in the 1950s. Their findings were different and often contradictory, for example, Staffeld  and RuscIn recent years, the use of eye tracking technology in the study of driver behaviour has been growing and expanding, as the ease of using this technology, its accuracy, and the quality and usability of the acquired data have vastly improved. It seems that the opportunities for eye tracking use in researching driver distractions are endless. For this reason, the purpose of this paper is to collect and analyse the studies carried out so far, which specifically examined distractions of drivers’ visual attention using eye tracking equipment. The literature review will focus on the methodological aspects of included scientific contributions to determine the ways in which eye tracking had been used in relevant research up to now. Moreover, we will analyse this narrow field of scientific research using basic scientometric procedures to determine the authors and topics that are prevalent in the field. Based on this, a summary of the main findings about the state of the research field will be given with suggestions for future use of eye tracking in the research of drivers’ visual attention and distractions will be presented. When looking for previous scientific publications using eye tracking to analyse distractions that affect the driver while driving, Scopus and Web of Science databases were used. The search was performed in July 2019. These two databases were selected because they are the most commonly used, but at the same time differ in their coverage . Therefopresent only literature reviews; focus on theoretical aspects of using eye tracking, and conceptual papers;focus on the technical aspects of eye tracking technology or present patents;suggest the use of eye tracking technology, but do not demonstrate direct use of the technology in research;study modalities other than car road transport, and papers devoted to autonomous vehicle use;use eye tracking technology for research into drivers’ visual behaviour during driving without specifically studying distracting factors, e.g. development of a model for predicting distracted driving or driver drowsiness or researching gaze patterns of drivers in general;do not deal directly with examining driver distraction, but rather use eye tracking to examine design features of various elements in the traffic environment or vehicle, e. g. the design of traffic signs, changes in road geometry, user interface design of in-vehicle systems…In Web of Science, a search was performed using the search string in the Topic field, which includes the title, keywords, and abstract. The search returned 372 results. In Scopus, the search, which included paper titles, keywords, and abstracts, returned 429 results. After deleting duplicates, 572 publications remained. The publications were reviewed, researchers read the abstracts and, where necessary, the methodological part. All publications were independently reviewed by two researchers and the publications that both excluded were taken out of the literature pool immediately, while the publications that the researchers didn’t agree on were reread and debated upon. The literature pool included 103 publications after this step. In order to ensure inclusion of all relevant scientific publications, reference lists of the 30 top cited publications from the current literature pool were also reviewed to find more relevant scientific publications that were not identified based on Scopus and WOS search. Through this step, additional 36 publications were added into the literature pool. Taking into account the exclusion criteria, 139 scientific publications that present research of driver distraction with the use of eye tracking technology were selected to be included in the analysis. The process of selecting the included studies is shown in The literature analysis was performed in two steps. First, we focused on bibliometric analysis showing basic parameters such as publication year and source journals, and science mapping, which utilized the VOSviewer tool  Science Furthermore, the analysis focused on how the research presented in the papers used eye tracking technology to research driver distraction and what variables were most often used. Therefore, we gathered information about the observed distractions, independent and dependent research variables, type of eye tracking used, and whether the research was performed in a driving simulator or on real roads. Based on this, an analysis of the key elements of the included publications was performed and presented. Additionally, Even though eye tracking tools have existed for quite some time, their extensive use in researching driver distractions began rising after the year 2002 when yearly output on the topic of driver distraction research using ET began rising. Before that, only 9 publications were published. From 2011 on, a significant increase in output on the field can be seen with publishing activity reaching its peak in 2013. The overall trend of a growing number of publications is seen, as shown in Out of the 139 included publications, 33 were published in conference proceedings and 106 in 10 different scientific journals. The total number of unique sources of publications is 50. A detailed publication number for the most productive sources that published 3 or more publications from the literature pool is shown in To identify papers with the largest impact in the field, citations in the Scopus database were also examined. 14 publications have more than 100 citations with Strayer, Drews, & Johnston  being thCitation mapping was performed using the VOSviewer tool and is based on citations of 136 papers in the literature pool in the Scopus database. Each of the 136 publications is represented with a node (circle) and named with the first author’s surname and publication year on Figure 3According to van Raan , citatioCo-citation analysis analyses how often two publications are cited together in another publication. 4057 publications that were cited by publications in the literature pool of the present research were first identified , as well as keywords with a common meaning . This reduced the number of keywords to 951.The keywords with most occurrences were “eye movements” with 78 occurrences, “car drivers” with 68, and “human” with 62. All keywords that were used at least ten times (52 keywords) are shown in Author keywords are a subsection of all keywords that VOSviewer identified, these are the keywords identified by the authors as representative of the papers’ contents. VOSviewer identified 288 unique keywords in the literature pool. Once again, synonyms and keywords with a common meaning were identified and merged, which left 253 keywords for analysis input. If we set the minimum number of a keyword occurrence to three, 33 author keywords are included in the analysis, which is shown in A table that shows Authors, publication year, source, observed distractions, observed independent and dependent variables, number of participants, setting, and type of eye tracking used, can be found in In the analysed publications, some used driving simulators, some on-road setting, some both, and some utilized a simpler approach by showing pre-recorded video clips of driving situations to participants. Out of the analysed publications, research was performed in a real road setting in 44 publications, 81 publications utilized a driving simulator of various sophistication, four publications used both simulators and on-road settings, and nine publications used only video recordings. Out of the 134 papers that had information about the number of participants’ data included in the eye tracking analysis available, the range of participants is from one to 123. The mean number of participants is 28.96 with a standard deviation of 21.58. If we only look at research that was done in a driving simulator, the mean number of participants is 27.84 with a standard deviation of 17.02 , and research performed on real roads had a mean of 26.05 participants . Based on these statistics and taking into account the large standard deviations, we can conclude that the number of participants varies largely and that the research setting does not seem to have a direct influence on the number of included participants. As for the eye tracking technology used, we grouped the used technology into two broad categories: head-mounted, wearable eye tracking systems, usually in the form of glasses or sometimes implemented with a use of a helmet, and remote eye tracking systems of various configurations, ranging in sophistication from a basic camera that records eye movements and where eye tracking data has to be coded manually, to multi-camera dashboard set ups that automatically code eye movements onto a recording of the driver’s visual field. Out of the 139 included publications, 53 publications report results, obtained with wearable eye tracking systems  further proves the above finding and additionally forms six clusters of connected publications which are most often cited together or share common references.The amount of cooperation among authors in the field, especially outside of their primary co-authorship network, is relatively low as shown by the co-authorship analysis. The co-authorship scheme shows that some co-authorship clusters have formed but are interconnected only with occasional collaborations.Four keyword clusters can be identified. One presents research, focused on utilizing driving simulators; the second seems to be focused on evaluating visual attention while taking into account participant factors such as age, gender, and psychological factors; the third, smallest cluster, focuses on accident prevention; and the fourth, largest, focuses on safety and specific distractions and tasks. As expected, “eye movements”, “driver distractions”, “car drivers” and alike are the most commonly used keywords, and these are also keywords used in the most cited papers from the field as shown by the analysis of author keywords. A little under a third of the included papers present research, performed in real road conditions, other papers utilize driving simulators of various sophistication levels, prerecorded video recordings of driving situations, and four publications utilize both simulators and on-road research. On average, research includes roughly 29 participants, with the average number of participants being slightly higher for research in driving simulators , but given the large standard deviations, it does not seem that research settings influence the number of included participants.An overall analysis of the research variables points to the fact that cognitive distractions are most researched, followed by visual ones. Cell phones and various IVIS systems are at the centre of in-vehicle distraction research while advertisements and information signs dominate research outside the vehicle. Most papers only include one distraction or task type. In addition to eye tracking parameters, the effects of driver distraction are often analysed by using complementary variables, such as parameters of driving performance and task performance. Another point worth mentioning is the use of glances or fixations as the basic eye movement parameter. There seems to be a lack of consensus on the field on which unit of measurement to use. We did notice however that a lot of research lately uses the definition of glances and fixations as was put forward in the ISO standard on measuring driver visual behaviour , where Overall, this paper has shown that the field of eye tracking use in driver distraction research is an emerging field with space for improvement and collaboration. The included publications present the main publications in the field and the authors took every possible step to include as much relevant sources as possible, but a possibility exists that some relevant sources have nevertheless been omitted. We estimate however that the coverage of the resent literature review is sufficient to give meaningful insight into the state of the art on the topic of driver distraction research using eye tracking.  Future research recommendations that would fill the gaps as identified in the paper include performing research in real conditions, including a wider array of distractions and comparing them to one another, a larger number of participants, and increasing interdisciplinarity of the field with more author cooperation outside of their primary co-authorship networks. As new potential distractors emerge every day, we conclude that eye tracking is a good tool to evaluate the effects these distractors have on a driver and especially on his overt visual distraction.http://biblio.unibe.ch/portale/elibrary/BOP/jemr/ethics.html and that there is no conflict of interest regarding the publication of this paper. The authors declare that the contents of the article are in agreement with the ethics described in


According to the US Bureau of Labor Statistics, nurses will be the largest labor pool in the United States by 2022, and more than 1.1 million nursing positions have to be filled by then in order to avoid a nursing shortage. In addition, the incidence rate of musculoskeletal disorders in nurses is above average in comparison with other occupations. Robot-assisted health care has the potential to alleviate the nursing shortage by automating mundane and routine nursing tasks. Furthermore, robots in health care environments may assist with safe patient mobility and handling and may thereby reduce the likelihood of musculoskeletal disorders.This pilot study investigates the perceived ease of use and perceived usefulness (acceptability) of a customized service robot as determined by nursing students . This service robot, referred to as the Adaptive Robotic Nurse Assistant (ARNA), was developed to enhance the productivity of nurses through cooperation during physical tasks  as well as nonphysical tasks . This pilot study evaluated the acceptability of ARNA to provide ambulatory assistance to patients.We conducted a trial with 24 participants to collect data and address the following research question: Is the use of ARNA as an ambulatory assistive device for patients acceptable to nurses? The experiments were conducted in a simulated hospital environment. Nursing students (as proxies for nursing staff) were grouped in dyads, with one participant serving as a nurse and the other acting as a patient. Two questionnaires were developed and administrated to the participants based on the Technology Acceptance Model with respect to the two subscales of perceived usefulness and perceived ease of use metrics. In order to evaluate the internal consistency/reliability of the questionnaires, we calculated Cronbach alpha coefficients. Furthermore, statistical analyses were conducted to evaluate the relation of each variable in the questionnaires with the overall perceived usefulness and perceived ease of use metrics.Both Cronbach alpha values were acceptably high , indicating high internal consistency of the questionnaires. The correlation between the variables and the overall perceived usefulness and perceived ease of use metrics was moderate. The average perceived usefulness and perceived ease of use metrics among the participants were 4.13 and 5.42, respectively, out of possible score of 7, indicating a higher-than-average acceptability of this service robot.The results served to identify factors that could affect nurses’ acceptance of ARNA and aspects needing improvement . According to the American Association of Colleges of Nursing, there is a shortage of registered nurses (RNs) in the United States, which is expected to escalate due to the increase in health care demands and needs of baby boomers as they age . Robot-aRobots may assist with safe patient handling and mobility in health care environments. In recent years, robots have been used in hospitals to assist with surgical procedures, deliver medications, monitor patients, and assist with daily hygiene . HoweverIn order to off-load some of the physically demanding tasks assigned to nursing staff and prevent physical injuries, we have built a robotic nursing assistant, referred to as Adaptive Robotic Nursing Assistant (ARNA). ARNA is a custom-built service robot, which is capable of autonomous navigation in hospital environments and performing tasks as a nursing assistant. ARNA is an omnidirectional mobile robot constructed in-house and augmented with a 6-DoF (degrees of freedom) robotic arm . ARNA isThis study evaluated the acceptability of ARNA as determined by nursing students in scenarios where ARNA was used as a robotic patient walker. The experiments were conducted in a simulated hospital environment. Nursing students (as proxies for nursing staff) were grouped in dyads, with one participant serving as a nurse and the other acting as a patient. We conducted a phase 1 trial  to collect quantitative data and address the following research question: Is the use of a service robot as an ambulatory assistive device for patients acceptable to nurses? In this context, user acceptability was measured using the two subscales of the Technology Acceptance Model (TAM) ,11, thatAll nursing students (n=24) were enrolled in coursework in undergraduate and master’s entry accelerated second-degree nursing programs that included patient care in hospitals. Recruitment occurred through in-class invitations by nursing faculty. Subsequently, interested students notified the faculty to volunteer for the study. As compensation for participating in the experiments, students received course credit for clinical/research hours for an undergraduate research course or capstone clinical course.Student volunteers were required to have the physical ability to adequately perform the tasks administered in the study. It should be noted that disabilities were used as exclusion criteria only if the disability substantially interfered with the performance of the tasks . Approval to conduct the study was obtained from the university’s institutional review board. All volunteers gave informed consent.ARNA is an omnidirectional mobile robot constructed in-house and augmented with a 6-DoF robotic arm . ARNA isThe prevention of patient falls is a measure of quality care in hospitals and a priority in the daily work of nurses. When ARNA is utilized as a patient walker, the user interaction efforts (forces and torques applied to the handlebar by patient) are sensed by the force-torque sensor mounted underneath the ARNA’s handlebar and used to extract the user’s navigational intent. The user intent is then communicated to the robot’s control unit, which, in turn, propels the robot in the intended direction, thereby inducing the feeling in users that they are interacting with a light-weight walker. Apart from providing ambulation assistance and stability support, ARNA utilizes its robotic arm to carry along intravenous (IV) lines and other tethering medical equipment . During such assisted walking, ARNA’s navigation sensors enhance the user’s safety by avoiding collisions of the robot with the carried IV pole and with objects and humans in the environment. From a technical standpoint, a high level of intelligence and autonomy is required to collaborate with a nurse and perform these tasks. For this purpose, we have equipped ARNA with a variety of sensors including cameras, Kinect, laser scanner, bump sensors, infrared sensors, and ultrasonic sensors.The experiments were conducted at a simulation suite located at School of Nursing, University of Louisville.Before participants arrived at the experiment location, the setting and robot were prepared by the project personnel. Only 2 nursing students and the project personnel were in the simulation lab at any given time. To facilitate task comprehension, participants received thorough verbal instructions and a task demonstration regarding the experiment procedure.Participants worked in dyads, with one participant serving as a nurse and the other acting as a patient requiring walking assistance. A rectangular path was marked on the floor for the participants to follow while receiving gait assistance from ARNA. The general task of “patient” was to hold onto the robot handlebar and walk with the robot while following the marked path on the floor, and the task of “nurse” was to walk alongside the patient and robot in a supervisory role holding an emergency stop switch. While walking, ARNA carried along an IV pole using its arm, maintaining a safe distance between the pole and objects in the environment, the patient, and itself. The nurse was instructed to activate the emergency stop switch, which would bring the robot to a complete hold, should the robot come into close vicinity of other objects or any unforeseen dangerous circumstances. Before beginning of the trial, the patient reclined in a hospital bed, and the nurse stood by him/her, both waiting for the trial initiation. Pursuant to the initiation signal from the experimenter, the patient received assistance from the nurse to climb down the bed and hold onto the ARNA’s handlebar. When the patient verbally confirmed firm grasp of the handlebar and stable posture, the nurse deactivated ARNA’s emergency stop, allowing the robot to operate. Next, the patient followed the rectangular path marked on the floor while receiving support from the robot until he/she arrived back at the bed, at which point the nurse reactivated the emergency stop and helped the patient lie back in the bed. Each experiment set consisted of 9 trial runs per participant. Original dyads were retained for all trial runs.Following the ninth trial, the nursing students were given a survey  about their experience interacting with the robot and assisting the patient. Surveys were administered in the form of a questionnaire and as Likert scales (discussed in the following subsection). Subsequently, the participants’ roles were switched, thus providing the roles of nurse and patient to both participants, and another 9-trial set of experiment runs repeated for a total of 216 trial runs. The entire experiment lasted 6 days (2 dyads per day). Participant groupings and nurse/patient role orders were randomized to prevent any inherent biases.ttitudes and broke down the concept of external variables into cognitive instrumental processes  and social influence processes  [The TAM was originally developed by Davis in 1989 to predict and explain a user’s acceptance of information technology (IT) . The oriariness) . The TAMariness) . The TAMariness) ,16, althariness) . When reThis study used two subscales of the TAM , originally proposed by Davis in 1989 , to evalP values [In order to examine the internal consistency of perceived usefulness and perceived ease of use subscales of the TAM in this context, we calculated Cronbach alpha values . CronbacP values .We calculated a Cronbach alpha of .93 for the perceived usefulness dataset and .82 for the perceived ease of use dataset.P value=.03). Additionally, weak-to-strong multicollinearities were detected between the perceived usefulness and perceived ease of use variables. In particular, variables 1, 2, 3, 7, 8, and 9 exhibited weak multicollinearity (condition index<10), variables 4 and 6 had a moderate collinearity (condition index=43), and variables 10 and 11 demonstrated a fairly strong collinearity (condition index=70).The mean and SD for each item in the questionnaires, among the participants, are shown in This study evaluated the usefulness and ease of use of ARNA as perceived by nursing students in order to assess its acceptability and the influencing factors, as well as to identify areas needing improvement for future development of ARNA. The calculated Cronbach alpha (0.93 for perceived usefulness dataset and 0.82 for perceived ease of use dataset) demonstrates acceptable internal consistency of the questionnaires. The statistical findings of the perceived usefulness and perceived ease of use subscales indicate a moderate-to-high acceptance of ARNA by the nursing students. The general opinion of the participants about ARNA was positive, as the mean value for overall usefulness and ease of use were above average . Furthermore, the correlation coefficients between the individual questions and the overall perceived usefulness and perceived ease of use were moderately acceptable, suggesting the usefulness of the questions in examining various aspects of perceived usefulness and perceived ease of use metrics.In general, this study enhances our understanding of various aspects of ARNA in terms of its perceived usefulness and perceived ease of use and points out key aspects that require improvement in order to facilitate ARNA’s acceptability and adoption likelihood. For example, it is important to improve ARNA’s flexibility as suggested by its moderate mean value of users’ responses to question 9. Perhaps by providing more user interfaces to accommodate various interaction styles, nurses’ perceptions of flexibility could be enhanced. The participants’ responses to the other perceived ease of use questions, however, were fairly high, suggesting that the robot is easy to operate. This may be attributable to the fact that the robot autonomously regulates the gait speed, provides stability support and collision avoidance, and only requires nurses to supervise the gait assistance and respond in case of emergency situations.The mean participant response to variable 1 was fairly low, and the mean responses to variables 2-5 were moderate, indicating that participants did not completely agree that use of ARNA robot improves their job performance or saves them substantial time. This is, however, not surprising, as in its current capacity, ARNA still requires a nurse to accompany the robot and the patient during the walking assistance, which is as time consuming as using a nonrobotic walker, although the robot provides stability support and collision avoidance. Endowing the robot with a fully autonomous capability to provide walking assistance to patients without direct nurse supervision may enhance users’ perception regarding job performance improvement. Completely outsourcing the walking assistance to a fully autonomous robot may render a nurse more efficient as he/she would only need to oversee the gait assistance and would therefore be able to focus on other responsibilities.Simulation is a growing trend in health care education, and proxies are frequently needed to collect data in clinical settings for children or incapacitated patients. Preliminary acceptability data was needed before taking ARNA into a hospital or other clinical setting and testing it with busy health care providers and vulnerable patients. This simulated health care study using nursing students is viewed as a step forward in the evolution of ARNA as a tool for safe and quality patient care and as protection against musculoskeletal disorders among nurses.The outcomes of this study should be deemed preliminary for a number of reasons. First, we evaluated usefulness and ease of use of ARNA with a limited number of nursing students in a simulated hospital environment, and, hence, the results may not extend to the whole population of nurses and health care providers in real health care environments. Second, due to our experimental design, each participant served as both patient and nurse, which may have influenced the participants’ perception of the acceptability of ARNA. This experimental design may also have affected the participants’ decisions during the study, thereby affecting the study results.In addition, in this study, we were not able to collect and evaluate actual user behavior of the ARNA robot over a long time period due to the study’s preliminary nature, and, hence, perceived usefulness and perceived ease of use were used as proxies to predict adoption likelihood and usage of ARNA among nurses.The rate of physical injury and musculoskeletal disorders in nurses is higher than average as compared to other occupations, which is typically due to patient handling and mobility. Robots bear a great potential to off-load some of the physically demanding tasks of nursing staff and health care providers, and hence prevent physical injuries. However, nurses’ acceptance of robotic nursing assistants is essential and warrants comprehensive assessment in order to ensure adoption of this technology and its large-scale implementation in health care environments.This study evaluated the acceptability of our custom-made robotic nursing assistant, ARNA, with respect to the two subscales of the TAM, perceived usefulness and perceived ease of use , during a patient walking scenario. User surveys were administered to 24 nursing students who served as the study participants. We conducted the experiments in a simulated hospital environment, where 2 participants were paired together, one playing the role of a patient and the other acting as a nurse providing ambulatory assistance to the patient using a service robot that functioned as a powered walker. After the trials, the participants serving as nurses filled out questionnaires about their opinions regarding usefulness and ease of use of the ARNA robot. This study, to the best of our knowledge, is the first to examine the user acceptability of robotic nursing assistants, serving as a stepping-stone for further discussions about the sociotechnical and commercial landscape surrounding this technology.


Diabetes mellitus is a widely diffused chronic condition which impacts on several aspects of patients' lives. In the current clinical practice, the implementation in the clinical routine of monitoring systems of patients' outcomes has led to an increased generation and use of several measures for the assessment of patients' quality of life (QOL). Nevertheless, this construct appears to be particularly complex, and its operationalization is variable across different measures. The purpose of this paper is to offer an updated review of the diabetes-specific QOL measures present in scientific literature with a specific focus on the broad domains assessed.  A scoping review was carried out with the purpose of identifying the existing measures in literature and describing their implicit representation of QOL in diabetes care. Five different databases  were searched with a string including validation studies of adult-only, diabetes-specific QOL measures. Each measure was then qualified according to its structure, a qualitative assessment of the broad domains of QOL it comprises, and finally an overview of the psychometric properties of its first validation.  30 scales were identified and assessed. Theme analysis shows that QOL is operationalized with multidimensional surveys comprising of both mental, physical, and social health components. Some scales also consider the impact of societal attitudes, public policies, and context on QOL.  Several self-report measures of QOL specifically developed for diabetic patients exist in scientific literature. The present scoping review reports scales structure, broad domains of QOL, and development purpose. This may help in understanding the concept of QOL in diabetic patients and may also serve the purpose of guiding the reader in the choice of the most appropriate instrument or in the development of a new one. Diabetes mellitus is a widely diffused chronic condition: according to the latest edition available of the IDF Diabetes Atlas, in 2013, about 382 million people all over the world were suffering of diabetes, causing a yearly expenditure of at least 548 million US dollars [1C [Diabetes exposes people to both physical  and psychological complications ; it also has a direct impact on several social aspects and, more generally, on daily life  –5. Indee1C , 7.The impact of the disease and of treatment on all chronic patients' quality of life (QOL) and lifestyle is a key concern for both the patients themselves and their physicians. This is particularly relevant in the case of diabetic patients: the physical, psychological, and social burden of diabetes affects patients' self-care behaviors, disease management, therapeutic adherence, and, consequently, QOL .This leads, in the current clinical practice, to a more frequent use of tools to measure the level of patients' perceived QOL. The purpose is, generally, to collect patients' inputs about their quality of life priorities and expectations, and to personalize their therapy and clinical course. In particular, the evaluation of QOL, a construct that has been defined as “a general concept that implies an evaluation of the impact of all aspects of life on general well-being” , seems tHowever, despite the clinical and scientific agreement about the importance of giving voice to diabetic patients about their QOL, no clear consensus exists about the exact definition of such construct, of its dimensions and, even less, of the best operationalization and best measures to use. A deeper comprehension of this construct is then necessary, in order to develop better suggestions and election criteria to orient researchers and clinicians in the selection of the most reliable and specific measurement tool according to the specific patients' population and their assessment objectives. From a psychological point of view, it is important in the assessment of QOL to consider the impact the sickness, and its treatment, on physical, social, and mental well-being, as stated by the World Health Organization . HoweverMany instruments being used for the assessment of QOL in adult diabetic patients are developed for general use with different kinds of patients and may not be suitable for assessing the specific needs and experiences of diabetic patients. A previous literature review from Speight et al.  categoriUnderstanding how the construct of diabetic patients' QOL was operationalized in the development of such measurements, in order to disentangle implicit clinical and scientific representation of the phenomenon Furthermore, we reviewed existing QOL measures used in diabetes to propose a comprehensive and systematic descriptive framework of the methodological peculiarities of existent measures in order to support clinical choice and practice .On the basis of this premise, the present literature review was carried out with the main objective of identifying the measures present in scientific literature specifically developed for the assessment of QOL in adult, diabetic patients. In particular, we were interested in the following:Previous literature reviews of QOL measures in diabetes are more focused on either the structure and psychometric properties of the scales, possibly outdated, or reviewing measures for more specific targets  , 16–19.identification of the relevant studiesstudy selectiondata chartingdata report.For the purpose of this paper, we performed a scoping review as defined by Armstrong et al. . The metTo better refine and circumscribe results and findings, we decided to only consider studies of first validation . This choice is also related to the main focus of our analysis: i.e., disentangling the implicit representation of the QOL phenomenon in the first operationalization and conceptualization of the measurement. We also decided to only consider scales developed for adult patients. For similar reasons, and since the most recent literature review with a similar purpose we could find is dated 2009 , the timScopusWeb of Science Core CollectionMedlinePsycInfoCochrane Central Register of Controlled Trials.To identify all possibly relevant studies, we interrogated a selection of the most important scientific databases in the medical and psychological field:th and the 7th of February 2019. The research string was composed of five different queries:DiabetesAND Quality of lifeAND MeasureAND Development/validationAND NOT Exclusion criteria .Search was conducted between the 4Each query was composed of different synonyms (connected with “OR”). The exact code was different for each database, according to its peculiarities: nevertheless, the words and the logic were the same. Scopus research string is shown below:∗) AND TITLE-ABS AND TITLE-ABS AND TITLE-ABS AND NOT TITLE-ABS(Translating OR Translation OR Infant OR Child OR Adolescent OR Pediatric∗) AND  OR LIMIT-TO  OR LIMIT-TO  OR LIMIT-TO  OR LIMIT-TO  OR LIMIT-TO  OR LIMIT-TO  OR LIMIT-TO  OR LIMIT-TO  OR LIMIT-TO  OR LIMIT-TO ).TITLE-ABS which was then used for duplicate check after which two independent researchers (LP and MMC) made a title and abstract screening of the references removing papers according to the following exclusion criteria:After that, full-text selection—following the same criteria—of the studies was carried out to identify only the relevant papers. Conflicts were resolved by consensus.Specifically developed for diabetic patientsValidated on an adult sampleValidation study available in EnglishMeasuring quality of life or impact on quality of life: since there is not a single, acceptable definition of QOL on which there is agreement, we refrained from picking one. Moreover, since quality of life and health-related quality of life are often used interchangeably in literature , to avoiFinally, criteria for data extraction were defined. Scale names and data were extracted from both original and reviews. For each scale name, the first validation study was retrieved . Validation studies were once again screened to only select those who were relevant to our research questions according to the following criteria:(i)(a)Energy/fatigue Stamina Pain (feelings of pain)Sick/well Rest .Physical health:(a)Distress Mood Memory Attitude (items addressing the positive/negative attitude towards the sickness or the situation)Emotional regulation Mental health:(b)Social engagement Relationships Intimacy Discrimination (feeling oppressed or discriminated by others due to diabetes)Social health:(c)Meaning to life (being capable of finding a meaning in one's own life regardless of diabetes)Satisfaction Recreation Activities Life satisfaction/beliefs:(d)Access to services Public policies Societal attitudes (towards diabetes).Environment:First, we carried out a qualitative theme analysis of the items comprised in the scale in order to categorize the measures according to the broad domains addressed. It is always important to have in mind what domains and aspects of QOL one wants to evaluate and to choose a measure accordingly. While most validation studies report factors and domains assessed by the scale, different authors generally use a different terminology—which could make it difficult to compare two different scales. A qualitative theme analysis of the scales' items allows to compare the broad domains assessed and the specific aspects comprised. Since no specific, systematic framework for quality of life in diabetes seems to exist, we adapted the function-neutral health-related quality of life framework developed by Krahn and colleagues . This frQualitative theme analysis was carried out by LP and MMC by inspecting scales items and searching for keywords and keywords' synonyms referring to these broad domains. Retrieved keywords were then grouped under the pertaining broad domains and reported, to allow an inspection of the domains considered within a certain measure and of their conceptualization(ii) Then, we extracted bibliometric data, relative population, and structure of the scale; it is important while choosing a measure to be aware of the number of items (which can give a rough estimate of the time it takes to be filled), of its age and of the population it has been developed for as well as the purpose for which it was developed (iii) Finally, psychometric properties were assessed according to the guidelines provided by Terwee and colleagues .We then developed the data extraction plan and database. We extracted three different types of data from validation studies:A synthesis of the identification and screening process can be found in The interrogation of the databases returned 2854 papers, which were later reduced to 1845 papers after checking for duplicates.The screening of the titles and abstracts of the identified 1845 papers led to the selection of 36 papers potentially relevant for the purpose of the current study. Further screening of the full-text led to the subsequent removal of other 6 papers, leading to a total of 30 included papers eligible for data extraction. From these 30 papers, 70 scale names (with the corresponding references) were extracted. Each scale was briefly screened, and 27 scales were selected—according to the aforementioned criteria—for a more in-depth analysis. Three additional scales were also included in our results, derived from additional sources retrieved by the authors.Tables Every screened measure addresses at least two different broad domains, four on average. In particular, amongst the QOL measures, each one of them comprises at least an item referring to either the life satisfaction/beliefs broad domain, mental health, or social health with very few exceptions , while less of the included measures offer an assessment of physical health (13 out of 19). Regarding the impact of the environment or of the context on diabetic patients' QOL, most measures comprise some items regarding either the financial burden, access to services, or societal attitude, the only exceptions being DQOL, DTR-QOL, and W-BQ28. One label appears to be particularly relevant for the assessment of QOL in diabetes, which is “activities,” present in 16 out of 19; these labels represent all the items that are intended to measure a disruption in daily activities and the burden of the illness  on work on other daily routines. Also, items regarding distress or the impact of diabetes on relationships are common.For what concerns the “additional” measures we included in our study, assessing the impact of diabetes on daily life, there are indeed some differences. While some domains such as mental health are well assessed by all measures (with a particular focus on distress and mood) and some labels such as “activities” are very frequent as well, most of these measures do not seem to capture the importance of the environment, with only 3 measures  assessing either the easiness of access to services, the financial burden, or societal attitude. Nevertheless, for what concerns the 4 core broad domains, there are no big differences, even though the domain of social health is possibly underrepresented, when confronted with QOL measures, with only 6 measures investigating some aspects of social life and, in particular, diabetes' impact on relationships .From the selected scales, 3 are specifically validated for Type 1 patients only and 5 for Type 2 patients only; the remaining are validated on mixed samples or the specificity is not declared.The oldest scale retrieved is from 1988 , while Since no golden standard exists for the measurement of QOL, criterion validity was not assessed. Minimal Important Change (MIC) was not reported for any of the examined evaluation studies; for this reason, it has been impossible to report responsiveness. However, floor and ceiling effects were at times reported, which can provide some insight into the ability of the measurement tool to report change. While for the (arguably) most fundamental characteristics—internal consistency, construct, and content validity—most of the studies were well reported and met the criteria; the same cannot be said about test-retest reliability, floor/ceiling effects, and, in particular, interpretability. Many measures specific for the assessment of QOL in diabetic patients or assessing the disruption of diabetes on daily life exist in scientific literature, suggesting that—in order to avoid an unnecessary development of new instruments—it would be more suitable to choose an already existing and validated measure. The present review reports the broad domains of QOL assessed by diabetes-specific measures in order to help understanding how this complex, multifaceted construct is being measured by validated, scientific tools. Each instrument included in this review is a self-report scale, mostly consisting in various items grouped into different domains or subscales. This is coherent with the definition of QOL, a multidimensional and subjective construct , 14, 23,While in QOL measures the role played by Environment seems to be well represented, it is the most underrepresented domain amongst the additional measures we considered: this is probably the main difference between these two sets of measures, representing the importance of the context in which a patient lives for his/her QOL, while being of less importance when considering the impact of diabetes or treatment on his/her distress levels or disruption of daily life activities.Indeed, even though it is not considered a core domain of QOL by the function-neutral framework, but an ancillary domain , it is sMoreover, it is worth noting that while aspects regarding mental health are as much considered as those regarding physical health, the psychological representation of illness—namely its cognitive, attitudinal, emotional, and symbolic value—the patients' sense of hope or positiveness and his/her capacity or intention to attribute a meaning to the illness and to participate actively to his/her own care planning are rarely investigated and taken into consideration. This may imply that—at least to a certain extent—the underlying rationale behind QOL measurement is to assess the amount or the absence of negative aspects related to QOL, while ignoring the amount or presence of positive aspects and behaviors (such as patients' willingness to engage in active participation). This appears poorly in line with the increasing complexity of QOL self-assessment according to patients' experience: QOL cannot be reduced to the elimination of disease symptoms and therapy side effects, but it relies also on the level of psychological elaboration and acceptance of the disease condition mastered by the patient . MeasuriMost of the analyzed validation studies are well reported and describe measures that have good psychometric properties, even though some relevant and important information are often missing . By the way, it is worth noting that almost every validation study described the process of item generation as starting from, or integrating patients' points of view ; this good practice of patient participation to measures development is important since it contributes to content validity and, in particular, in the case of QOL, since it is a construct that—by definition, as already remarked—is subjective.Another important aspect to consider when evaluating the feasibility of using a certain measure in one's own study or clinical practice is the setting of validation: scales developed too many years ago—or in different cultures—may not actually be representative of today's life with diabetes, patients' needs, and perspectives. Also, it is important to keep in mind the context and the purpose for which the specific tool was developed: was it intended for clinical use, or instead for research? Is it patient-centered, treatment-centered, or diet-centered? While a clinically oriented measure could be used for research and vice-versa, different purposes generally require different characteristics.One final remark worth discussing regards measures' length: while quality of life is certainly a complex construct, composed of several components that may require a consistent number of items for a thorough assessment, it is also necessary to keep in mind the burden that a very long questionnaire (such as the 200+ items DCP ) exerts Finally, This scoping review has some limitations: first, we searched only those databased which we believed to be the most relevant to our research questions; second, even though we included precedent literature reviews in order to compensate for this, we decided to limit our research to the last 10 years, in order to obtain a manageable set of data. Additionally, our search was limited to such studies that have been published in English and for adult patients. This means that, potentially, relevant validation studies may have been missed by our review process. The use of an exclusion criteria (AND NOT) in the search string may have led to a bias in the identification of relevant studies.By the way, the main purpose of our research was to identify how the QOL construct has been operationalized in the context of diabetic care. We chose to analyze only the evidences from original, first validation studies, excluding further evidences of psychometric robustness: this probably means that for at least some of the described measures, some evidences regarding psychometric properties have been missed. The validation of a measurement tool is an iterative and complex process that generally requires several evidences and studies: considering only the first evidences of validity is limiting, and our analysis should not be considered comprehensive of this aspect, as this is not the principal aim of this paper. The assessment of psychometric evaluation was carried out according to the guidelines from Terwee et al.  which, eMany self-report measures of QOL specifically developed for diabetic patients exist in scientific literature, suggesting that before an effort is done to develop a new measure, an attempt should be done to select an already existing and validated instrument, in order to avoid useless duplication and redundancy. This scoping review reports broad domains of QOL that are assessed by measuring tools available in scientific literature specifically developed for adult diabetic patients. All the four core broad domains of QOL seem to be covered by existing measures. Nevertheless, there seems to be a lack of measures including an assessment of the environment around the patient and/or of his positiveness/positive behaviors. This also suggests the need for further validation studies aimed at developing more complete assessment instruments. The medium length of the scale retrieved, however, also suggests the need for future attempt to reduce the length of used measures and or to develop shorted and more user-friendly ones.Finally, for the purpose of guiding the reader in the choice of the most suitable measure, other information such as scales structure, development purpose, and some first evidences of psychometric validation were reported.If an adequate measure could not be found in literature such that it suits the needs of a certain specific purpose, the results from the qualitative theme analysis could be used in order to understand which aspects of QOL are most commonly assessed in diabetic patients and which, on the other hand, are currently superseded in order to guide the development of a new measure.


Following the spread of the infection from the new SARS-CoV2 coronavirus in March 2020, several surgical societies have released their recommendations to manage the implications of the COVID-19 pandemic for the daily clinical practice. The recommendations on emergency surgery have fueled a debate among surgeons on an international level.We maintain that laparoscopic cholecystectomy remains the treatment of choice for acute cholecystitis, even in the COVID-19 era. Moreover, since laparoscopic cholecystectomy is not more likely to spread the COVID-19 infection than open cholecystectomy, it must be organized in such a way as to be carried out safely even in the present situation, to guarantee the patient with the best outcomes that minimally invasive surgery has shown to have. Following the spread of the infection from the new SARS-CoV2 coronavirus in March 2020, several surgical societies have released their recommendations to manage the implications of the COVID-19 pandemic for the daily clinical practice.The recommendations on emergency surgery have fueled a debate among surgeons on an international level.The SICE , ACS-Italy Chapter (American College of Surgeons), AICO , CRSA , SICG , SICOP , SPIGC , and the WSES (World Society of Emergency Surgery) have come out in favor of a rational analysis of the issue, especially about the choice of the surgical techniques to be implemented, preferring a “selective” approach that does not exclude the use of laparoscopy a priori but, instead, strongly considers it.This approach is based on an analysis of the organization of human and logistical resources within which each of us operates, and takes into account the surgical skills that each surgeon has developed in the non-COVID era.The British Intercollegiate General Surgery Guidance on COVID-19 stated that during the COVID-19 pandemic, “whenever non-operative management is possible (such as for early appendicitis and acute cholecystitis), this should be implemented” [Other surgical societies, however, including the SICE, the Society of American Gastrointestinal and Endoscopic Surgeons (SAGES), and the European Association for Endoscopic Surgery (EAES), have recommended a more patient-centered and hospital-centered approach –4.There is still an essential ongoing debate on the specific question: “should we change our surgical indications for urgent conditions in this global situation?”Reports from China told us that asymptomatic COVID-19-positive patients undergoing surgery go against unfavorable clinical outcomes, characterized by increased mortality and pulmonary complication rates .This issue, along with the increased non-surgical care load that has impacted, and in some cases continues to impact profoundly on the activity of many hospitals in the world and also in Italy, has favored a change in the therapeutic approach for some surgical diseases, including acute cholecystitis (AC).The debate that arose from these recommendations has revealed some further concerns about the possible evolution towards the aggravation of AC during non-operative treatment, such as to require a higher level of care following the failure of antibiotic therapy. A level of care that would not be possible to achieve in specific contexts with intensive care units still occupied by patients with COVID pneumonia.As a scientific society, we must remember that therapeutic indications are established based on the best scientific evidence available at the moment and organizational choices must be founded on the evidence that science and research make available to health systems. This underlying assumption should never be forgotten, and even the possible revision of the surgical indications for the COVID-19 emergency (or other future emergencies) should take into account this fundamental principle.Therefore, it is necessary to refer to the best available evidence to choose the therapeutic strategy for our patients, and do not allow the pressure imposed by the emergency conditioning to change our choices.Laparoscopic cholecystectomy (LC) remains the treatment of choice for AC, even in the COVID-19 era.All current guidelines recommend LC as the gold standard of therapy for AC, because of the better results in terms of mortality, morbidity, and postoperative hospital stay compared to open cholecystectomy (OC) –8.The Italian guidelines, promoted by SICE in 2012 in collaboration with all the leading Italian scientific societies  and our Several studies have emphasized that many toxic components of the surgical smoke may endanger the operating team’s health.Blood-borne viruses  are known to be present in the plume produced by electrocautery and other energy devices , 11. HowNo evidence emerged suggesting that the risk of COVID-19 infection related to LC may be higher than that of OC, neither for the patient nor for the health professionals. Therefore, this working group does not consider that patients should be denied the benefits that high-quality studies have shown to be associated with LC. We recommend surgeons to take the necessary safety measures to reduce the risk of viral diffusion in the operating theater and ensure that patients continue to benefit from advantages of laparoscopic surgery .If, on the one hand, laparoscopy contains the surgical smoke within the peritoneal cavity, on the other, the pneumoperitoneum evacuation could put the staff at risk of infection.We suggest filtering the pneumoperitoneum through filters able to remove most viral particles. The ULPA (ultra-low particulate air) filters are extremely efficient to filter the SARS-CoV-2 virus whose diameter is about 0.06–0.14 μm. According to the ISO standard 29463 (issued to harmonize the European Standard EN 1822 and the US MIL-STD-282), an ULPA filter must have a ≥ 99.9995% efficiency at filtering particles with a MMPS (most penetrating particle size) of 0.12 μm. The MMPS is the particle that the filter is less efficient to remove. Smaller particles are filtered with an even higher efficiency. The use of these filters is recommended .It is crucial nowadays to examine the evidence concerning the timing of LC for AC, which compares the results of “early” cholecystectomy with those of “delayed” cholecystectomy, that is carried out after a period of conservative therapy to overcome the acute phase.Early cholecystectomy is recommended in all the guidelines mentioned above, based on the results of several meta-analyses of randomized controlled trials that compared the two different approaches. It has been demonstrated that early cholecystectomy  has not shown inferior results compared with the delayed one in terms of morbidity, mortality, and conversion rate .Therefore, early cholecystectomy is preferable to the delayed, for its shorter overall length of hospitalization .The equivalency of the two strategies in terms of morbidity, mortality, and conversion rate cannot justify the systematic use of delayed cholecystectomy. During the COVID epidemic, it may instead be desirable to postpone the surgical act away from the epidemic period, even at the cost of greater use of resources of the health system (length of stay).The equivalency in terms of morbidity and mortality between the two approaches can be a solid basis for more extensive use of delayed cholecystectomy, based on the analysis of the human and logistical resources of the hospital in which each of us works, the organizational pathways adopted, and the local epidemiological situation.It is mandatory that during the conservative treatment period, attention must be paid to monitoring sepsis parameters and pain progression despite appropriate analgesic therapy. The danger of progress of the septic state and the risk of progression towards the gangrene, emphysematous cholecystitis, or the rupture of the gallbladder may, anyway, require emergency cholecystectomy.If it is true that in the pre-COVID period, cholecystectomy in patients classified as high risk according to the various guidelines has a mortality rate that can reach 19% , clearlyBoth the incidence of AC and the mortality from COVID-19 are higher in elderly patients. Although elderly patients are more likely to present with different comorbidities that complicate any postoperative course, early LA for AC is safe and effective in this group of patients, albeit burdened by increasing conversion rates .The Italian guidelines  on LC  and the The analysis of the international literature, despite being mainly based on observational studies with a low level of evidence, demonstrates a high mortality rate for patients undergoing percutaneous gallbladder drainage. High mortality was also shown in recent extensive retrospective analyzes , 17.Moreover, the CHOCOLATE trial, a randomized controlled trial that had been started to compare the results of percutaneous drainage vs cholecystectomy, was prematurely terminated because the ethical problems arising from the observation of the high mortality in patients who underwent percutaneous drainage did not allow the further continuation of the study .As indicated, the execution of a percutaneous cholecystostomy  takes place, as specified above, after the failure of conservative therapy, which constitutes the first therapeutic strategy in these particularly fragile patients.Of all the options currently listed in the literature , percutaneous transhepatic cholecystostomy is generally the preferred one, due to its simplicity of execution, safety, and reduced costs.The optimal timing for performing percutaneous cholecystostomy is widely debated. However, when the cholecystostomy is carried out within 24 h from the onset of the clinical presentation is associated with fewer complications in terms of bleeding and lower hospital stay . HoweverFor the remaining patients not eligible for surgery, it is common practice to proceed with cholecystostomy if the patient does not improve within 1–3 days of starting antibiotic therapy.We maintain that, since laparoscopy is not more likely to spread the COVID-19 infection than open surgery, it must be organized in such a way as to be carried out safely even in the present situation, to guarantee the patient with the best outcomes that minimally invasive surgery has shown to have. In the case of patients unfit for surgery, percutaneous transhepatic cholecystostomy may be considered after the failure of conservative therapy with antibiotics.


Ball possession, distance, and market value of the teams had no influence on success. Overall, most of the critical success factors and those with the highest impact on winning close games were defensive actions. Moreover, the results suggest that direct play and pressing were more effective than ball possession play. The study contributes to a better understanding of success factors and can help to improve effectiveness of training, match preparation, and coaching.Research on success factors in football focusing on national teams is sparse. The current study examines the success factors during the World Cup 2018 in Russia and the World Cup 2014 in Brazil. A total of 128 matches were analyzed using a generalized order logit approach. Twenty-nine variables were identified from previous research. The results showed that defensive errors ( To understand the mechanisms underlying success in football is critical for coaches, players, managers, journalists, and other stakeholders. This understanding is in football as crucial as in other sports, but it is still a challenge to determine what leads to success in football. Various attempts have been undertaken to identify and quantify indicators of performance, but results vary and are partly inconsistent. Most studies focused on domestic leagues consisting of club teams, while studies on the performance of national teams at tournaments are sparse. Only 11 studies involving data of success factors from a World Cup were published in recent years , passing, and possession  or based on goals . Despite providing more information, the goal-based approach does not perform better than the results-based approach Goddard, . An alteThe goal of this exploratory study is to identify the success factors for the FIFA World Cup 2018 in Russia and the FIFA World Cup 2014 in Brazil using an elaborated statistical approach. Twenty-nine variables will be investigated using a results-based approach. This will be the first study to include market value as a success factor of a FIFA World Cup.www.whoscored.com. The data for duel success were gathered from www.kicker.de. The data on both websites are provided by OPTA. The reliability of the OPTA data lies between 0.92 and 0.94 , a binary dummy variable for home advantage was included in the analysis. To control for the strength of the opponent, the last FIFA coefficient prior to the tournament was used  for all 128 matches were collected from ed FIFA, . The touhttps://www.optasports.com/insight-for-fans/opta-s-event-definitions/  and 20 matches as unbalanced . The 108 matches were analyzed twice, since the home team (first mentioned team) on the schedule is not playing at home except for the 12 matches mentioned before. Hence, this analysis is based on 216 observations.A 2 = 260.7; p = 0.000); therefore, the assumption of proportional odds is violated  were calculated , with one defensive error decreasing the probability of winning by 10.25%. One additional shot from a counterattack increased the chance of winning by 6.51% . However, duel success (%) and goal efficiency showed to be important as well and highly significant . None of the contextual variables showed a significant impact. However, the contextual variable home advantage had the highest positive value  of all variablesThe marginal effects for the outcome “win” of all analyzed variables are displayed in The seven significant variables including the 95% confidence intervals are also shown in The purpose of this research was to identify success factors in the games played at the Football World Cups in 2018 and 2014. The significant positive success factors during the World Cup 2018 and 2014 were shots from counterattack, duel success (%), goal efficiency (%), clearances and tackles success (%). On the other hand, defensive errors and crosses had a significant negative impact on the probability of winning. Despite that none of the contextual factors in this study were significant, it is still worth noting that the effects of those variables were substantial.Of the significant variables, four variables related to defense  were significant. Two variables related to goal scoring [goal efficiency (%) and shots from counterattack], and one variable related to passing and organizing (crosses) showed significant influence. No contextual variables were significant.p < 0.001). Despite being an intuitive result, defensive errors were rarely analyzed in recent studies, and this study permits a quantification of the impact. Lepschy et al. (p < 0.001). However, duel success has the lowest standard deviation of the following significant defensive factors and has the lowest range. Therefore, it could be argued that despite the higher value, the positive effect of duel success is limited. Furthermore, the percentage of successful tackles was a significant positive success factor as well . However, previous research has yielded inconclusive results about whether the percentage of successful tackles is significant or not  on success. This confirms previous research by Carmichael et al. . Moreover, the conversion of shots into goals is shown to be a very important success factor. In agreement with previous research, it was shown that goal efficiency has a significant positive effect on winning .Besides the multitude of significant defensive factors, the analysis revealed that there are also actions of offensive performance that can make the difference. Notably, each shot from a counterattack increased the chance of winning by 6.51% (p < 0.05). Again, this confirms previous research  were widely studied in the past, and the results showed mostly a significant positive effect on success , goal efficiency (%), and tackles success (%) are more important than the quantity of single factors, a finding that is supported by Collet . FinallyThe results of this study have various implications for coaches of national teams but could also be helpful for coaches of club teams. Our findings point toward aspects that can make the difference at high-level football matches. Shot accuracy during matches is critical and should be properly addressed in training sessions. The development and utilization of apt training methods could be beneficial for the goal efficiency and eventually lead to more success. Accuracy instead of quantity should be the maxim. Furthermore, more effective ways to lower the probability of defensive errors should be found and implemented in specific training sessions. Next to technical and tactical skills, the improvement of endurance, speed, and mental strength could be critical in this context. To increase the duel and tackles success rate, specific training methods could be utilized, and players should be focused on the importance of these factors in match preparations. Substitutions to accommodate for physical and mental fatigue of the starting formation could also contribute to a lower error rate and can help to win a match [see also Njororai  and NjorBy interpreting the results of this study, four restrictions have to be taken into account. First, the sample size contained only matches of national teams during a tournament including only 128 matches. Therefore, the possible generalization of the results is limited. In addition, the sample consisted of matches from the group stages and knockout stages. The tactics used in the different stages could have interfered with the results. Second, the variable short passes was dropped in favor of reduced collinearity. Any effects of this variable were not accounted for. Third, the variable market value of the starting formation was gathered from a public website and is not a standardized factor. Fourth, the data were collected from third parties, and the reliability of their collection process was checked in previous research for a specific sample, which showed 0.92 and 0.94 and not directly for the obtained samples (see Sample section).With regard to future research, the study points toward several aspects that need further investigation. The influence of ball possession needs to be analyzed in more detail. This study showed no significant influence, which is in agreement with previous research Collet, . HoweverFuture research also needs to analyze the effects of the distance covered, since results are inconsistent. In addition, the negative impact of crosses should be analyzed. Lepschy et al.  found siMethodologically, predictive analyses are the methods of choice. However, alternative methodological approaches such as social network analysis (Wäsche et al., The study showed that defensive errors had the strongest influence on the probability of winning or losing a football match during the World Cups 2018 and 2014. In addition, goal efficiency, duel success in percentage, and tackles success in percentage were shown to be of high significance. It appears that efficiency factors are more important than single factors alone. Shots from counterattacks and clearances also revealed a positive impact. In contrast, the number of crosses showed a negative impact on winning. In total, four different variables related to defense, two variables related to goal scoring, one variable related to passing and organizing, and no contextual variables were significant. Interestingly, shots from counterattacks, tackles, and duel success are significant predictors of success, whereas ball possession and passes are not significant. This could be an indicator for the assumption that tactics dominated by pressing could be a better strategy than tactics solely based on ball possession. However, national teams and club teams cannot readily be compared due to different contexts such as the competition format. Future research needs to determine possible differences. In addition, the ambiguous results for ball possession and number of crosses from different studies needs to be addressed in future research. Further research on success factors, building on existing knowledge and utilizing apt methods, will further contribute to the knowledge of coaches, managers, and other practitioners to improve team performance in football.The datasets generated for this study are available on request to the corresponding authors.Studies involving animal subjects: No animal studies are presented in this manuscript. Studies involving human subjects: No human studies are presented in this manuscript. Inclusion of identifiable human data: No potentially identifiable human images or data is presented in this study.HL contributed to the conception and design of the study, the data collection, the data analysis and interpretation, the drafting the article, and gave the final approval of the version to be published. HW and AW contributed to the conception and design of the study, the data analysis and interpretation, the drafting the article, and gave the final approval of the version to be published. All authors contributed to the article 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.


Acute myeloid leukemia (AML) is a fatal blood cancer that progresses rapidly and hinders the function of blood cells and the immune system. The current AML diagnostic method, a manual examination of the peripheral blood smear, is time consuming, labor intensive, and suffers from considerable inter-observer variation. Herein, a machine learning model to detect and classify immature leukocytes for efficient diagnosis of AML is presented. Images of leukocytes in AML patients and healthy controls were obtained from a publicly available dataset in The Cancer Imaging Archive. Image format conversion, multi-Otsu thresholding, and morphological operations were used for segmentation of the nucleus and cytoplasm. From each image, 16 features were extracted, two of which are new nucleus color features proposed in this study. A random forest algorithm was trained for the detection and classification of immature leukocytes. The model achieved 92.99% accuracy for detection and 93.45% accuracy for classification of immature leukocytes into four types. Precision values for each class were above 65%, which is an improvement on the current state of art. Based on Gini importance, the nucleus to cytoplasm area ratio was a discriminative feature for both detection and classification, while the two proposed features were shown to be significant for classification. The proposed model can be used as a support tool for the diagnosis of AML, and the features calculated to be most important serve as a baseline for future research. Acute myeloid leukemia (AML) is the deadliest of the four types of leukemia, accounting for 11,000 annual deaths in the US with an average five-year survival rate of 28.7% . DetectiProgressing rapidly, AML can be fatal within months or even weeks if not diagnosed and treated immediately . Hence, In developing countries such as Nicaragua, diagnosis takes 29 days to be reached due to lack of access to healthcare and physician delay ,11. The A multitude of segmentation techniques, morphological features, and machine learning classifiers have been employed in the literature. Kazemi et al.  segmenteThe purpose of this research is to develop a model capable of accurately detecting and classifying immature leukocytes in AML cells from an imbalanced dataset into four types  with a random forest algorithm. Detection and classification of immature leukocytes will greatly aid the clinical diagnosis of AML. To add to the limited set of color features used for classification of leukocytes , two newLabelled images of leukocytes from the peripheral blood of 100 AML patients and 100 healthy controls were collected from the dataset assembled by Matek et al.  in The CThe methodology consisted of four main phases: segmentation, feature extraction, classification, and calculation of feature importance. During segmentation, binary masks of the cell and nucleus were obtained for each image. A total of 16 features were extracted to be inputted into a random forest algorithm for classification between immature and mature cells, as well as further classification of immature cells. Finally, the importance of each feature was calculated using the metrics of the random forest algorithm. The project was coded in the Python programming language  with numThe objective of segmentation see  was to oA similar process was carried out to obtain a binary mask of the nucleus. Since the nucleus was always the darkest component, the image was converted to gray scale for the best discrimination of the nucleus, as shown in The proposed segmentation procedure successfully segmented 1070 out of 1274 images (83.99%). The majority of failed segmentation can be attributed to background cells overlapping with the ROI and stain obscuring the ROI. Given that the dataset was collected for a study with a CNN, which does not require segmentation and feature extraction, the segmentation results are acceptable. The purpose of feature extraction was to obtain a set of descriptors that are discriminative for classification of leukocytes. From each image, 16 cytomorphological features were extracted, which could be divided into four categories: nucleus size, nucleus shape, elliptical features, and color features. Nucleus size features consisted of area, perimeter, area to perimeter ratio, equivalent diameter , and nucIn the above equations, fficient . We propfficient  are alsofficient ,16. All A random forest algorithm was chosen for classification because of its higher performance with imbalanced data when compared to other machine learning classifiers ,32,33,34TP), true negative (TN), false positive (FP), and false negative (FN). Binary classification performance metrics, namely accuracy (Equation (6)), precision (Equation (7)), recall (Equation (8)), and specificity (Equation (9)), were defined as follows:In the classification step, binary classification between immature and mature leukocytes was first performed, followed by classification of immature leukocytes into four types. For binary classification, 80% of the data in the features matrix was used for training and 20% was reserved for testing of the model. For multiclass classification of immature leukocytes, 70% of the data was used for training and 30% was used as the testing set. All splitting of data into training and testing sets was randomized. A random forest classifier with 100 trees was initially tested and evaluated for both binary and multiclass classification. Binary classification was quantitatively evaluated on the testing set with accuracy, precision, recall , and specificity as performance metrics. The performance metrics were based on the possible outcomes of classification: true positive . The Gini importance of a feature in a random forest algorithm is defined as the mean reduction in Gini impurity across all decision trees caused by the feature . For eacAfter the random forest model was trained, the performance was evaluated with the previously listed performance metrics. Compared to the accuracy and recall of the model, the precision and specificity are slightly lower due to the number of false positives. Although not ideal, high recall is preferred over precision for fatal diseases such as AML. The area under the curve of the ROC curve (AUC-ROC) is 0.98, which is comparable to the current state of art model in the study by Matek et al. , which aFor multiclass classification, the initial random forest model obtained precision and recall above 85% for all classes except the promyelocyte class. The optimized model, which was constructed with average precision as the scoring metric, obtained precision above 65% for all classes see . The modThe results are superior to previous state of art , which aThe lower performance on the promyelocyte class can be attributed to the fact that promyelocytes and myeloblasts are consecutive steps in the cell lineage of myeloid cells, therefore the two classes share morphological characteristics . LikewisBased on Gini importance, the most important features for detection see  and clasThe N:C ratio was calculated to be a significant discriminator for both detection and classification of immature leukocytes. This finding is supported by previous research that classified hemocyte precursors . For claTo overcome the limitations of the manual diagnosis methodology for AML, a random forest model for automatic detection and classification of immature leukocytes was presented. The model was capable of detecting immature leukocytes with 93% accuracy and 0.98 AUC-ROC, which is on par with the current state of art . FurtherApplications of the study are two-fold. While the proposed model cannot diagnose AML alone, it can be used as an effective support tool for doctors to reduce the time and cost required for the diagnosis of AML. The high accuracy of the model in binary classification demonstrates that the model can serve as an efficient screening tool, which can rapidly identify potentially cancerous cells for further examination by a doctor ,37,38. TAn important future direction is to gather a comprehensive dataset and develop a machine learning classifier that can classify all the types of immature leukocytes and work with imbalanced data. Future studies can expand on this work by calculating and ranking the importance of additional morphological features for the classification of leukocytes. Improving the discrimination between similar cell types, such as myeloblasts and promyelocytes, is also an avenue for future work. The difficulty of differentiating myeloblasts and promyelocytes can potentially be overcome by identifying features that are especially discriminative for the two cell types and training a specialized model to discriminate between the two cell types. Research on leukemia detection has obtained very promising results, and further work is required to develop systems that can be completely integrated into the clinical diagnosis method. Contributions of this study are an accurate model for detecting and classifying immature leukocytes, as well as calculation of the most important morphological features, which provide a basis for future research on computer-aided diagnosis of leukemia.