Background: Observational studies support an association between periodontitis (PD) and atherosclerotic vascular disease, but little is known specifically about peripheral arterial occlusive disease (PAOD). Objectives: To systematically review the evidence for an association between PD and PAOD. Data Sources: Medline via PubMed. Review Methods: We searched the Pubmed database for original studies, case reports, case series, meta-analyses and systematic reviews that assessed whether there is an association between PD  and PAOD . The reporting of this systematic review was in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement following the Population, Intervention, Control, and Outcome (PICO) format. Results: 17 out of 755 detected studies were included in the qualitative synthesis. Nine studies demonstrated associations between PD and PAOD, and two studies reported associations between tooth loss and PAOD. Six studies addressed the pathomechanism regarding PD as a possible trigger for PAOD. No study that dismissed an association could be detected. Odds ratios or hazard ratios ranged from 1.3 to 3.9 in four large cohort studies after adjusting for established cardiovascular risk factors. Conclusions: The presented evidence supports a link between PD and PAOD. Further studies which address the temporality of PD and PAOD and randomized controlled intervention trials examining the causal impact of PD on PAOD are needed. Although our results cannot confirm a causal role of PD in the development of PAOD, it is likely that PD is associated with PAOD and plays a contributing role. As a consequence of demographic changes and the proliferation of the western lifestyle, peripheral arterial occlusive disease (PAOD) has developed into a widespread disease with globally over 200 million persons affected ,2,3. PAODespite the benefit of modern medicine, to date, there is no curative treatment available, and all non-invasive or invasive approaches aim to address the symptoms or disease progression. Hence, screening and prevention programs have gained more attention to identify new PAOD risk factors. It is well known that PAOD is associated with tobacco use, diabetes, high cholesterol, and higher age . With reNowadays, there is scientific consensus that the development of PAOD is also associated with chronic subclinical inflammation ,7,8. ThePD has been shown to be associated with atherosclerotic vascular disease. At least four basic pathogenic mechanisms are currently hypothesized that may explain how PD may promote atherosclerosis : (1) OraTherefore, the goals of this systematic review were: (1) to collect evidence for an association between PD or tooth loss and PAOD from the published literature and (2) to look for clinical studies that investigated the pathomechanism that might be involved in a potential cause-effect relationship between PD and PAOD.Seven hundred and fifty-one studies were detected by the search formula (shown in the method section), and four additional studies were identified through other sources and added in December 2018. Seven hundred and two studies were excluded following the screening algorithm (see Methods section). Full-text articles were assessed for eligibility. Thirty-six studies were excluded because no full-text article was available, the paper did not match the eligibility criteria, or it had limitations regarding the definition of PAOD or PD. Following application of the eligibility criteria, 17 studies out of the detected 755 studies were included in the qualitative synthesis. Nine studies demonstrated associations between PD and PAOD and two studies associations between tooth loss and PAOD. Six studies addressed the pathomechanism regarding PD as a trigger for PAOD and were included in the discussion. No study that dismissed an association was detected. p = 0.003) of developing PAOD was observed in men with clinically significant PD at baseline compared to men with no or only mild PD at baseline. Subsequently, an evaluation of the prospective Health Professionals Follow-up Study [The first study to demonstrate an association between PD and PAOD was a longitudinal study published by Mendez et al. in 1998 . One thoup Study , which wup Study .In a cross-sectional evaluation of data from the National Health and Nutrition Examination Survey (NHANES), 172 of 3585 participants were diagnosed to have PAOD. PD was significantly associated with PAOD with an odds ratio (OR) of over two in men and women . MoreoveMunoz-Torres et al.  assessedp = 0.01). PAOD patients also had more missing teeth than non-PAOD participants , while no significant difference was found with respect to the clinical attachment loss between PAOD patients and non-PAOD participants  [A recently reported meta-analysis that included a total of 4,307 participants from seven independent studies, confirmed these findings. The study showed a significantly increased risk of PD in PAOD patients compared with non-PAOD patients  .p = 0.031). The results also indicated that PAOD patients had higher CRP levels (p = 0.0413) and a higher mean decayed missing filled teeth (DMFT) index value (p = 0.0002) along with an elevated number of missing teeth (p = 0.0459) compared to the control group. The study also addressed the potential mechanism of the association. The CRP level was significantly higher (p = 0.0413), and there was also a difference in the decayed-missing-filled-teeth (DMFT) index (p = 0.0002), with a higher number of missing teeth (p = 0.0459) in the PAOD group compared to the control group. However, there were no significant differences regarding the frequency of bacteria in serum and subgingival plaque samples.Association between PD and PAOD was not only detected in cross-sectional and longitudinal studies, but also in several case-control studies. A strong association was observed by Soto-Barreras et al.  based onA strong association between PAOD and PD was also reported by Calapkorur et al.  who founIn a case-control, retrospective study based on chart reviews, Molloy et al.  evaluateChen et al. , observePhorphyromonas gingivalis  [For this systematic review, six studies were found that addressed the potential pathomechanism that may be involved in the association and may explain how PD could induce or aggravate PAOD see : (1) Perd in PD) .In a blinded randomized controlled trial, Li et al.  could shThis systematic review supports that PD is associated with PAOD, which may lead to the hypothesis that PD may be a risk factor for PAOD. To date, many studies describe associations between periodontitis or oral disease and atherosclerosis in general. Therefore, we wanted to specifically focus on studies that concern peripheral vascular disease (PAOD) as a potential consequence of periodontitis in this systematic review. However, it has to be stated that the published literature is not absolutely certain about the term PAOD for “peripheral artery occlusive disease”. In publications, it is frequently used for lower extremity artery disease (LEAD). Indeed, other peripheral localizations, including the carotid and vertebral, upper extremities, mesenteric and renal arteries, are also frequently affected, mainly by atherosclerosis, and complete the family of peripheral arterial diseases . In addiAll studies that were included in this systematic review could detect an association between PD or tooth loss and PAOD irrespective of study design, outcome measure, and study population.This supports that the consistency of the association is high. It must be noted, however, that there is inherent bias, since risk factors for PAOD also can cause PD. Standardized effect sizes, which provide a measure of the strength of the association, have mostly been determined by logistic regression analyses and reported as ORs together with 95% CIs. After making adjustments for age, gender, and other cardio vascular disease (CVD) risk factors, the reported ORs ranged from somewhat over two in NHANES  to over Taken together, these results suggest that severe PD increases the risk for PAOD to a similar extent as PD increases the risk for cardiovascular events, which with respect to the latter was shown to be ≈1.20-fold in adjusted models from meta-analyses of prospective cohort studies ,34. SmokIf PD is a causal or, at the least, an important contributor involved in the pathogenesis of PAOD, one would expect that PD precedes the onset of PAOD. However, only very limited information exists with respect to the temporality of both diseases. According to results from the prospective Health Professionals Follow-up Study, tooth loss seemed to precede PAOD, since the incidence of PAOD was most strongly associated with tooth loss in a period of 2 to 6 years prior to the occurrence of PAOD . The facThe plausibility of a causal or, at least, an important involvement of PD in the development of PAOD mostly relates to experimental data showing that inflammation is involved in the pathophysiology of atherosclerosis, which in turn is involved in the development of PAOD. This inflammation could be caused by a direct involvement of periodontal pathogenic bacteria, which enter the vascular wall via the bloodstream. The study by Figuero et al. used nested polymerase chain reaction (PCR) to detect three periodontal pathogens in subgingival, vascular, and blood samples. Although positive test results were obtained in high fractions of the subgingival samples (>70%) and the vascular and blood samples (7 to 11.4%), patients with and without PD did not differ with respect to the levels of the targeted bacteria. Therefore, a direct involvement of the bacteria seems inconclusive at this stage.P. gingivalis  could play a role [P. gingivalis–specific T-cell lines from atheroma lesions isolated from PD patients. However, the study included only two patients, and the origin of the lesions remained unclear.The studies by Nishida et al. 2016  and Armiy a role . SupportANRIL/CDKN2B-AS1 [cis and trans mechanisms. How precisely ANRIL contributes to the risk of PD and PAOD on the molecular level is currently unclear.It is evident from the results section that our search-strategy yielded only a few publications that dealt with the pathomechanism of the association between PD and PAOD. A large fraction of the published mechanistic studies concerned animal, in vitro and ex vivo studies describing the link between PD and vascular sclerosis in general rather than that between PD and PAOD specifically. These studies were, however, not eligible for this review based on the pre-defined exclusion criteria shown in KN2B-AS1 ,40. The P. gingivalis from atherosclerotic tissue. In addition, it should be noted that long-term treatment with antibiotics, such as roxithromycin and rifalazil, showed no benefit in patients with an established diagnosis of PAOD [So far, many, but not all, studies demonstrated the presence of bacterial DNA in a large number of atheromas, but only very few could demonstrate the successful isolation of viable bacteria from an atherosclerotic plaque. In fact, to the best of our knowledge, there is not a single study available that could demonstrate isolation and cultivation of viable  of PAOD ,42. Nevehttp://www.prisma-statement.org. We employed the Population, Intervention, Control, and Outcome (PICO) format to answer the following PICO questions:This systematic review considered all studies listed in PubMed until 30 September 2018. For additional studies, we double-checked in EMBASE and supplemented with additional hits obtained from Google Scholar. Grey literature was not part of the review process. It was reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement (PRISMA) . For theIs PD associated with the occurrence of PAOD?Population = All patients with PD  who were detected in the selected literatureIntervention = NoneComparison = Patients with and without PDOutcome = PAOD of the lower extremityWe first determined a list of synonyms and MeSH-terms  for PAOD and PD. Using these lists, we defined the following search-formula.AND κ) demonstrated good agreement between the two reviewers (κ = 0.9)  and one with oral health expertise (US). Reviewers were blinded to each other results. Both reviewers screened all papers selected by the search formula to identify inclusion criteria. Any disagreements between reviewers at each stage of selection were resolved by consensus. Cohen’s kappa coefficient (κ = 0.9) . The stuκ = 0.9) .Following this algorithm, we decided whether the eligibility criteria were met; first by title, and if the title led to an uncertainty regarding the eligibility criteria, additionally by the abstract. If there was still uncertainty, the whole paper was read. Animal studies, studies that were published in non-English, studies that did not correspond to original papers, case reports, case series, meta-analyses, or systemic reviews were excluded. In addition, studies on coronary or carotidal/cerebral sclerosis or vascular sclerosis were excluded in general because the aim of this systematic review was to focus on PAOD. Studies describing an association between PD  and PAOD  were included and further processed according to the PRISMA flow diagram . StudiesThe risk of bias was assessed by using the Newcastle–Ottawa Scale  for caseIn conclusion, the present evidence supports a link between PD and PAOD. Further studies which address the temporality of PD and PAOD are warranted. Thus, a causal, or at least, an important contributing role of PD in the development of PAOD can currently not be confirmed but may be suspected. Clearly, the ultimate proof of causality would depend on data from randomized controlled invention trials to show that treatment of PD can diminish or even prevent PAOD. Such data does, to the best of our knowledge, currently not exist.


Introduction: Child mental health is known to be influenced by parental work hours. Although literature suggests that parent-child interaction mediates the association, few studies have directly measured the parental time of returning home from work. We analyzed data from a school-based survey to examine the association between parental time of returning home from work and child mental health.Methods: We used a sample of 2,987 first-year primary school students derived from the Adachi Child Health Impact of Living Difficulty (A-CHILD) study that examined the impact of family environment and lifestyle on child health in Adachi City, Tokyo, Japan. We analyzed the associations between reported parental time of returning home and the continuous Strengths and Difficulties Questionnaire (SDQ) scores using multivariable regression modeling.Results: Children whose parents both returned home late (later than 6 p.m. for the mother and later than 8 p.m. for the father), or at irregular times, had higher scores in total difficulties , the “conduct problems” subscale , and the hyperactivity/inattention subscale  compared with children whose parents both returned home earlier. Mediation analyses indicated that the percentage of the total association between parental time of returning home and the SDQ scores, which was mediated by parent-child interaction, was 20% (95% CI: 10 to 46) for total difficulties, 17% (95% CI: 7 to 49) for conduct problems, and 23% (95% CI: 11 to 52) for hyperactivity/inattention.Conclusions: Late or irregular returning home times for both parents had an adverse effect on child mental health, and the relationship was partly mediated by reduced frequency of parent-child interaction. Globally, mental disorders are responsible for 8.5% of disability-adjusted life years among children aged 5–9 years old . AttentiAs the labor force participation rate for mothers with children increases in countries such as Australia, Europe, and North America, more researchers have explored the relationship between parental employment and child mental health . EmpiricAmong dual-earner families, maternal and/or paternal working hours in the evening, night, or at irregular times have been shown to increase the risk of behavior problems in children , 8. SuchWhile most literature has assessed the influence of parental work schedules on child mental health, little research has directly examined the role of the time that parents return home from work. Several factors other than work schedules may affect the time that parents spend with their children. For example, 77% of workers in Japan had an average commute time of 79 min per day traveling to and from work, with the longest commuting time reported in the Tokyo area . In addiJust like other OECD countries, the labor force participation rate for mothers with children is increasing in Japan. In 2016, 54.0% of Japanese women with preschool children were engaged in work, an increase of 17.6% from 15 years earlier . Time spIn this study, we examined the association between parental time of returning home from work and child mental health among primary school students in Japan. We then estimated to what extent parent-child interaction mediates this association.We used data from the first wave of the Adachi Child Health Impact of Living Difficulty (A-CHILD) study, conducted by Adachi City Tokyo Medical and Dental University, and National Center for Child Health and Development, in Tokyo, Japan. Adachi City is located north of the center of Tokyo Metropolis. The overall rate of children receiving financial assistance for school supplies and school lunches for financial reasons in Adachi City was 35.8% (2015) and higher than the metropolitan average (21.6% in 2014), and the life expectancy in Adachi City  was shorter than the metropolitan average  in 2010. The A-CHILD study is an ongoing longitudinal study of children in public kindergartens and public elementary and junior high schools in Adachi City, Tokyo, and their families. The A-CHILD study was designed to examine the health status and living conditions of children, to investigate the impact of family environment and lifestyle on child health, and to understand the mechanisms through which household socioeconomic conditions influence child health. The first wave of the survey included first-grade children from all 69 public elementary schools. Data collection took place in July 2015 in six schools (pilot survey) and November 2015 in the other 63 schools (main survey). Data were collected using a parent/caregivers' questionnaire. The questionnaires were distributed to the children in class by the teachers, and the children took the questionnaire home for their parent/caregivers to fill out. The children then brought the completed questionnaire to school to submit to the teachers. Informed consent was obtained from the parent/caregiver by including a question at the beginning of the questionnaire about their participation agreement in the study. As of April 2015, there were 5,383 first-grade children in public elementary schools, of whom 28 either moved out of the city or were absent for long time at the time of the survey. Another 888 children did not submit the completed questionnaire, and the parents of 173 children refused to participate. Additionally, three children did not have any valid answers. Therefore, 4,291 children were included in the dataset.The A-CHILD study was reviewed and approved by the Institutional Review Board at the National Center for Child Health and Development. This study was also approved by the Institutional Review Board at Tokyo Medical and Dental University.http://www.sdqinfo.com. The SDQ consists of 25 child behavioral attributes that were divided into five subscales, namely emotional symptoms, conduct problems, hyperactivity/inattention, peer relationship problems, and prosocial behavior. Based on parents' ratings, five subscale scores and a score for total difficulties were calculated. To calculate the total difficulties score, all but the prosocial behavior subscale score was summed. Each subscale score can range from 0 to 10, and the total difficulties score can range from 0 to 40. Higher scores for the total difficulties score, emotional symptoms, conduct problems, hyperactivity/inattention, and peer relationship problems indicated a higher likelihood of psychological difficulties, whereas higher scores for prosocial behavior indicated the presence of prosocial behavior. The SDQ scores are strongly correlated with the Rutter scores and the Child Behavior Checklist scores , without impact supplement version, for the parents of 4–17 year olds available at t scores , 17. Relt scores , 19.The time parents returned home from work was assessed by two questions for each parent: “What is your present employment status: full-time employment, part-time employment, self-employment, side work, other, or unemployment?” and, for parents who were employed, “What time do you usually return home from work: before 6 p.m., between 6 and 8 p.m., between 8 and 10 p.m., 10 p.m. or later, irregular time due to shift work, or irregular time due to frequent overtime?”. We first dichotomized time of returning from work into “late or irregular”  and “not late” . We used 6 p.m. for mothers and 8 p.m. for fathers as the cut-off point, because they were the national average returning home times for working females and males, respectively . CombinaWe created a parent-child interaction score by combining the frequency of nine types of activities performed together between a child and parents   and frequency of the child eating dinner alone  . The parent-child interaction score ranged from 0 to 39.Child sex, child living together with siblings and grandparents, parental age, education, and employment, household income, respondent of questionnaire, and respondent's psychological distress [assessed using Kessler 6 ] were usn = 3,511) contained in the main survey data of the A-CHILD study were eligible for inclusion in the analyses. A child was excluded if data documenting any of the SDQ scores, the parental time of returning home, and/or any components of the parent-child interaction score were missing (n = 524). After excluding those with missing values, 2,987 children were included in the analyses.All children living with both parents (2), for parental time of returning home pattern were estimated.First, we compared the characteristics among children with different parental time of returning home pattern by using chi-squared test. Second, we calculated the mean SDQ scores and parent-child interaction scores across the categories of parental time of returning home pattern, and then compared them by ANOVA. The effect sizes, i.e., the proportion of variability explained . Nonparametric bootstrapping was applied to calculate p-values and 95% confidence intervals for the proportion that was mediated.Third, a multiple linear regression model was used to examine the relationship between SDQ scores and parental time of returning home pattern. To explore the potential mediation of the associations by parent-child interaction, we added parent-child interaction scores to the regression models, and compared the regression coefficients from models with and without the parent-child interaction variable. Regression coefficients were adjusted for all the covariates. All missing covariates were given dummy coding. To determine the extent to which the association between SDQ scores and parental returning home times was mediated by parent-child interaction scores, we performed mediation analysis  . We firsFurther, we conducted sensitivity analyses of SDQ variables by categorizing the SDQ scores as normal, borderline, and clinical based on the distribution of the scores among Japanese children aged 4–12 years of age , and usen = 532) were older (p = 0.004) and more educated (p = 0.014); and fathers who returned home late or at irregular times  were younger (p ≤ 0.001) and more educated (p < 0.001). Annual income was higher (p < 0.001) and grandparents were more likely to live together with the family (p = 0.093) in households where mothers and/or fathers returned home late or at irregular times. Level of psychological distress was similar between parental time of returning home categories (p = 0.89).Table p = 0.024 and 0.008, respectively).Table 2) of parental time of returning home pattern were 0.005 (95% CI: 0.000 to 0.010) on total difficulties, 0.003 (95% CI: 0.000 to 0.008) on conduct problems, and 0.003 (95% CI: 0.000 to 0.009) on hyperactivity/inattention before controlling for parent-child interaction score.Multivariable regression analyses Table  indicateResults of the mediation analyses Table  suggestep = 0.001 and p = 0.019, respectively), and both the borderline and clinical categories of hyperactivity/inattention , although we found significant reduced risk of the borderline category of emotional symptoms (p = 0.043) (Supplementary Table Sensitivity analysis, that is, multinomial regression analyses of the categorical SDQ scores, suggested that late parental time of returning home was also significantly associated with the increased risk of the clinical categories of total difficulties and conduct problems (This study explores the relationship between parental time of returning home and child mental health among primary school students in Japan. It is the first to examine the impact of parental time of returning home from work using a population-based study in Tokyo, Japan. While previous research has assessed the influence of parental work schedules on child mental health, little research has directly examined the role of the time parents return home from work.Our results suggest that children in households where both mothers and fathers returned late or at irregular times have a higher risk of showing mental health problems, in particular, conduct and hyperactivity/inattention problems. These difficulties constitute externalizing problems, which can pose a substantial burden to individuals and their families –25. ThisThe results also showed that, to a small extent, parent-child interaction partially mediated the association between parental time of returning home, and conduct problems and hyperactivity/inattention problems. This finding is consistent with earlier studies that reported the mediation effect of quality and/or quantity of parent-child interaction on the relationship between parental working hours and child externalizing behavior problems –9. We arAs shown in the sensitivities analyses, parental returning home late or at irregular time might have stronger effects on the risk of clinically severe child difficulties than on borderline level. Thus, although the effect size was small in the linear analysis, we confirmed that later parental retuning home may have clinical impact on behavior problems of the offspring. We also found reduced risk of borderline level of emotional symptoms, which might be because parents retuning home late or at irregular time may not be able to detect borderline level of emotional symptoms of children. Further research is needed to confirm the association using longitudinal study.2 = 0.001, which can be interpret that effect of fish and processed food explained 0.1% of child SDQ (It should be noted that the effect sizes of parental time of returning home pattern on child mental health was small, that is, later parental time of returning home had impact for 0.5% or less on child behavior problems. Previous observational studies on risk of SDQ among children also reported smaller effect size. For example, a previous study of the associations between early childhood fish and processed food consumption and conduct problems assessed by SDQ reported the effect sizes of ηhild SDQ . Thus, aThis study has a few limitations. First, we used parental reports of returning home times, which may contain measurement errors due to self-reporting. Second, this study does not address the use of child care services after school. Additional adjustment for use of child care services, therefore, might the magnitude of the adverse effect of parental time of returning home reported in this study. Third, this study uses cross-sectional data that cannot account for changes in parental time of returning home and child mental health over time, meaning that reverse causation is likely. Some evidence also suggests that parental employment can affect child mental health through parental well-being , especiaIn conclusion, children whose parents both returned home late or at irregular times have a higher risk of showing conduct problems and hyperactivity/inattention problems, and the relationship was partially mediated by reduced parent-child interaction. Future research should explore the variety of positive and negative reasons why parents returned home late that relate to the household environment.TF conceived the study. MO, AI, TK, and TF conducted the survey. MK analyzed data and wrote first draft. TF finalized manuscript. All authors approved the final manuscript.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.


Introduction: Different kinds of shared and activity-based offices are common today and employees' experiences, perceived health, well-being, satisfaction, and productivity have been studied in different types and sizes of environments.Objectives: In this study we aimed to determine employee satisfaction with a multi-space office. We also aimed to find associations between satisfaction with working space and both individual and social well-being.Methods: A total of 91 employees from a multi-space office shared by six municipality-owned companies answered a self-administered questionnaire. Frequencies, percentages, averages, and minimum and maximum values are used to describe the results. We used cross-tabulation and Pearson's Chi-Square test to study the associations and linear regression analysis to create a model describing the variability of workspace satisfaction.Results: The employees were most satisfied with the workspace furniture (82% of respondents) and most dissatisfied with workspace acoustics (44%). Workspace satisfaction was associated with self-satisfaction, good self-perceived future work ability, and good recovery. As regards social factors, workspace satisfaction was associated with good atmosphere among colleagues and good social capital. Satisfaction with acoustics was also associated with good self-perceived future work ability, recovery, and good social capital. Social capital best explained the general variation in workplace satisfaction.Conclusions: Many individual- and social-related well-being outcomes, and especially social capital, were associated with workspace satisfaction. To maintain workplace satisfaction and well-being, attention should be paid to the design, functionality, and management of the used workspaces. Different kinds of activity-based working environments are common in work life today . Among oAccording to several studies, the positive aspects of multi-space offices are their technical aspects, such as their aesthetic overall appearance, as well as effective information transfer, interaction, and communality. Some problems are related to technical solutions such as inadequate working or storage space, problems with mobile technology, or lack of privacy. Often, problems are also reported as concentration difficulties, interruptions, and irrelevant speech noise , 4–6, 8.Bodin Danielsson et al.  report tLindberg et al.  found thIt has been established that cleanliness, natural lightning, orientation, and regulation of lighting of the workspace have significant impact on the satisfaction of employees with any kind of the workspace . Some inAccording to our knowledge, workspace satisfaction has not previously been studied in relation to the social characteristics of the work community, such as atmosphere between colleagues or social capital. The most commonly used definition of social capital is that of Putnam , accordiIn this study, we aimed to determine employee satisfaction with a multi-space office. We also aimed to study the associations between satisfaction with working spaces and well-being. The hypothesis we consider is: Satisfaction with working space is associated with (1) self-satisfaction, (2) better recovery, (3) good perceived future work ability, (4) better working atmosphere, and (5) social capital.The office in this study was shared by six municipality-owned companies, who moved there in 2016, approximately a year before the research started. Thus, the research population was a newly formed work community, the members of which had previously worked in different kinds of offices ranging from open-plan offices to single-room offices. Some of the subjects had previous experience of open and flexible working environments, while others had not. The organizations did knowledge-oriented work and service work in the fields of regional development, regional planning, transportation, welfare services, infrastructure, trade, and innovation. The smallest organization had six employees, whereas the largest one had ~70. One of the organizations also had workers and contractors in other locations besides the shared office. The employees worked in different teams according to the varying demands of their work. Thus, we believe that good social capital might be an important factor affecting how satisfied employees are with a space solution that supports this kind of work.The office space had recently been renovated and designed for the purposes of knowledge-oriented work. It was basically an activity-based office or a multi-space office. Some organizations practiced hot-desking, while others had fixed desks for each employee. The office space was divided by glass walls so that two of the organizations had separate areas, one of which was behind an inner door. Three of the organizations shared a large open-plan space. In addition to this, there were silent spaces, phone booths, and cubicles for small meetings, a large recreation area, and a conference center.We emailed the questionnaire to all employees of the six organizations in the workspace in Webropol format. We sent it in January 2018, and a reminder twice in February. Information letter on voluntary participation, confidentiality, etc., was included in the survey. Every participant had the opportunity to ask anything about the survey in an information session. Participants knew that they could interrupt their participation at any time without cause. A written informed consent was not required as per local legislation and institutional requirements due to the assumption that by replying to the questionnaire they will give permission to analyzing the data. This study followed all guidelines and instructions of the Finnish National Board on Research Integrity and because we did not have individual health-related questions, ethical approval was not required according to local legislation and national requirements. This study was not medical research, and questions were not deeply related to individual health but rather to well-being.The main outcome variable was a modified version of the Indoor Environment Quality questionnaire developed in the Center for the Built Environment at the University of California . We askeWe selected six items to study social capital at work . These iThe atmosphere in the office was elicited by a question from the Copenhagen Psychosocial Questionnaire : Is therWe used IBM SPSS 25-statistical software for the statistical analyses.Before the analyses, we merged the categories of some variables (see below) because some categories had too few responses and we wanted to avoid the loss of statistical power.The descriptive part of the results has been reported in terms of frequencies and percentages, averages, and minimum and maximum values.p < 0.05.We examined the relationship between workspace satisfaction and well-being using cross-tabulation and Pearson's Chi-Square. The statistically significant level was set to We created a sum variable from the questions describing workspace satisfaction so that the numerical codes for the 10 sub-questions were summed up and divided by the number of questions. Cronbach's alpha of the sum variable (describes the unity of questions) was 0.85. We also created sum variables for its different parts: lighting (α = 0.81), acoustics (α = 0.73), design (α = 0.61), and workspace furniture (α = 0.77). One question elicited general satisfaction with one's own workstation. The sum variable was also formed from the social capital variable's five sub-questions in the same way (α = 0.85).Workspace satisfaction was described by a three-grade sum variable: dissatisfied (1–4), partly satisfied (4.1–5), and satisfied (5.1–7). The classification for a variable describing satisfaction with lighting, acoustics, design, and workspace furniture was dissatisfied (1–3), partly satisfied (3.1–5), and satisfied (5.1–7). Overall satisfaction with one's own workstation was categorized as: dissatisfied (1–2), partly satisfied (3–5) and satisfied (6–7). In cross-tabulations, we combined dissatisfied and partly satisfied into one class. The sum variable on social capital was: disagree (1–2.4), neither disagree nor agree (2.5–3), agree (3.1–5).The classifications were based on the background information of the issue and mathematical calculations.A model describing the variability of workspace satisfaction was created using linear regression analysis. In the model, the main outcome variable was the sum variable of workspace satisfaction. It was increased to the 2nd power, so that it had normal distribution. We standardized the model according to age and each person's own estimate of ability to work until retirement age. We wanted to have person's own estimate of future work ability as an individual characteristic in the model. Age was induced as it might affect the associations. We then added the well-being variables into the model alternately.N = 91). The respondents were from all the different sized organizations and their number varied by organization from 4 to 33. Most of the respondents were full-time and permanent workers. About one-fourth were temporary workers. Approximately, one-fifth of the employees (21%) had started working for the same employer in the fall of 2016 or later. The mean age of the respondents was 46 ± 11 years (between 26 and 62). Women comprised 68% (n = 62), men 26% (n = 24) of the respondents, and 6% (n = 5) identified as non-binary or did not answer the question. There were 16 supervisors (18%). More than half of the respondents (62%) reported having worked in the last 12 months outside the office. Only about one-fifth (22%) of the respondents worked at a fixed workstation, on a fixed computer and did not travel or telework at all.The response rate was 49% (The respondents were most satisfied with the workspace furniture (82% of respondents) and lighting (71%) . They wep = 0.054).Background variables were not related to workspace satisfaction, but the supervisors were more satisfied with their own personal workstation more often . Three-quarters of those in management or supervisor positions felt that they recovered well from work, compared to only 41% of those in other positions (p < 0.05).Background variables were also not associated with well-being variables, except perceived recovery. Men reported recovering well after the work day more often than women  of those dissatisfied with their workspace were satisfied with themselves  as well, whereas about three fourths .Self-perceived future work ability was more positive among those who were satisfied with their workspace than among the dissatisfied: Three out of four satisfied respondents believed they would continue until retirement age, whereas more than half (57%) of the dissatisfied were unsure (p < 0.01).Those who were satisfied with the workspace felt that they recovered from their workload well (62% of satisfied), compared to 26% of those who were dissatisfied (p < 0.001).Of those who were satisfied with the workspace, almost half (45%) also felt that they always or almost always had a good atmosphere between colleagues. In contrast, more than half (54%) of the dissatisfied and partly satisfied respondents sometimes or rarely experienced this  (p < 0.0p < 0.05).Those who were satisfied with the workspace more often had a high individual-level social capital than those who were dissatisfied  (Most of those who were satisfied with acoustics (81%) believed they would be able to work in their profession until retirement age, whereas almost half of those who were dissatisfied (45%) were unsure ( < 0.05) .p < 0.05).We found a strong association between dissatisfaction with acoustics and recovery from workload, clearly more than half (62%) of the dissatisfied respondents experienced poor or moderate recovery, whereas three quarters (76%) of those who were satisfied recovered well (p < 0.01).More than half (52%) of those who were satisfied with acoustics had high individual-level social capital, compared to about a quarter of those who were dissatisfied (26%)  and the most dissatisfied with workspace acoustics (44% of respondents). Workspace satisfaction was associated with good self-satisfaction, good perceived future work ability, and recovery. Of the social factors of workspace satisfaction, we found associations with good atmosphere among colleagues in the whole office and good social capital. Satisfaction with acoustics was also associated with good self-perceived future work ability and recovery, in particular with high individual-level social capital. Social capital best explained the general variation in workplace satisfaction.In line with the results of Kim and Dear  concerniWorkspace satisfaction was associated with recovery from workload. Perhaps when one is satisfied with one's workspace and its functionality, this is also reflected in good recovery after the work day. Good recovery was also associated with acoustic satisfaction. Not many studies have examined recovery while working in different kind of workspaces. However, in a study by Lindberg et al. , both thWe found a strong association between workspace satisfaction and a good atmosphere in the workplace community, not just between colleagues in their own organization. The good side of working in multi-space offices is the increased possibility of interaction with colleagues, so the importance of an atmosphere that supports good interaction is essential. However, Bernstein and Turban  found thSelf-perceived future work ability and recovery were associated with acoustics satisfaction. The association between social capital and acoustics satisfaction was even stronger than the association between social capital and general workplace satisfaction. How can an acoustic work environment be improved, and thus also well-being? The attenuation of disturbing noises has been studied and technical solutions recommended e.g., , 29]. Co. Co29)].The results of this study support our hypothesis of the association of social capital with workspace satisfaction. However, based on this study material, we cannot say whether good social capital increases workspace satisfaction in a multi-space office solution or whether workspace satisfaction increases social capital. However, these things are associated with each other. Thus, social capital can be supported by designing (joint) functional workspaces appropriately.Research is needed on whether a change in work in the form of, for example, a new working space solution can act as a source of inspiration and increase social capital. Associations between multi-space offices and well-being are interesting, not only in terms of job satisfaction, but also in terms of recovery and better perceived work ability, and these things should be identified as the basis for planning.We did not ask about the content of work thoroughly enough. The content of work may have varied somewhat, both within and between organizations, which may have affected the responses. However, all the participants did expert/knowledge work. It may be more difficult to do planning tasks that require concentration in a multi-space office, whereas interactions and coordination are emphasized in customer service work, to which a multi-space office might be better suited . Only abOnly about half of the employees (49%) of all the six organizations responded to the questionnaire. However, the respondents were from all the organizations and the age range was rather large, so the results can be considered at least preliminary. The modeling of workspace satisfaction was hampered by the fact that many respondents did not report their age, and that the number of supervisors and workers per organization was small.The analysis used in this study does not reveal the direction of the effects. It might be that when a workspace is considered good, well-being improves; or that those who have good well-being are more satisfied working in a multi-space office environment.Workspace satisfaction, and individual as well social well-being, measured in many different ways, and especially social capital, are associated with each other. It is worth paying attention to the design, functionality, and management of the used workspaces, in order to maintain workplace satisfaction and well-being.The datasets generated for this study will not be made publicly available for ethical reasons. We do not have the permission of the organizations involved in the research.Ethical review and approval was not required for the study on human participants in accordance with the local legislation and national requirements. Written informed consent for participation was not required for this study in accordance with the national legislation and requirements.SL, SK, HA, and PH contributed to the study conception and design, data collection and interpretation, manuscript preparation and review. JU contributed to analyzing and writing the results.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.


Sigfox has become one of the main Low-Power Wide Area Network (LPWAN) technologies, as it has attracted the attention of the industry, academy and standards development organizations in recent years. Sigfox devices, such as sensors or actuators, are expected to run on limited energy sources; therefore, it is crucial to investigate the energy consumption of Sigfox. However, the literature has only focused on this topic to a very limited extent. This paper presents an analytical model that characterizes device current consumption, device lifetime and energy cost of data delivery with Sigfox. In order to capture a realistic behavior, the model has been derived from measurements carried out on a real Sigfox hardware module. The model allows quantifying the impact of relevant Sigfox parameters and mechanisms, as well as frame losses, on Sigfox device energy performance. Among others, evaluation results show that the considered Sigfox device, powered by a 2400 mAh battery, can achieve a theoretical lifetime of 1.5 or 2.5 years while sending one message every 10 min at 100 bit/s or 600 bit/s, respectively, and an asymptotic lifetime of 14.6 years as the message transmission rate decreases. Low-Power Wide Area Networks (LPWANs) have recently emerged as a category of wireless technologies suitable for enabling Internet of Things (IoT) applications in a diversity of domains . LPWAN tOne of the most popular LPWAN technologies is called Sigfox . This teMany academic studies focus on evaluating the performance of Sigfox ,13,14,15This paper analytically models device current consumption, device lifetime and energy efficiency of data delivery with Sigfox. In order to capture a realistic behavior, our model is based on measurements conducted on a real hardware platform. The model presented allows to determine the influence of crucial Sigfox parameters and mechanisms, such as the uplink physical layer data rate, payload size, unidirectional or bidirectional communication, and message losses, on Sigfox energy performance. Our evaluation results illustrate the energy performance and trade-offs of Sigfox. Among others, we have found that a Sigfox device running on a 2400 mAh battery can achieve a lifetime of 1.5 years (at 100 bit/s) or 2.5 years (at 600 bit/s) while transmitting one uplink message every 10 min, and an asymptotic theoretical lifetime of 14.6 years as the message sending rate decreases. The remainder of the paper is organized as follows: Many published works focus on Sigfox performance evaluation. Relevant performance parameters considered by researchers include coverage, capacity and energy consumption ,7,8. WhiAs of the writing, a few analytical models of Sigfox current consumption, device lifetime or energy cost of data delivery have been published ,13,14,15Morin et al. present a device lifetime comparison for a wide range of wireless IoT technologies . AssuminHernández et al. provide an analytical model that considers uplink and downlink communications, with a characterization of power consumption states based on measurements carried out on a real platform . Using aThe rest of papers considered in this literature review provide an analytical energy consumption model, but they do not use it to estimate the device lifetime. Ogawa et al. present an analytical model for confirmed uplink communications, with the goal of estimating the energy cost of data delivery per year . Only trBased on our literature review, we conclude that our paper is the first one that provides a detailed and comprehensive analytical model of Sigfox device current consumption, device lifetime and energy cost of data delivery, considering real Sigfox device hardware behavior, the different communication settings and mechanisms , and the impact of frame losses. This section provides an overview of Sigfox. The section is organized in two parts. The first one describes the Sigfox network architecture. The second one focuses on the Sigfox radio interface, covering physical communication characteristics, as well as protocol features. The Sigfox network architecture comprises devices, base stations and a core network . DevicesSigfox supports unidirectional and bidirectional communication over unlicensed spectrum. In Europe, the bands 868.00 MHz–868.60 MHz and 869.40 MHz to 869.65 MHz are used for uplink and downlink transmission, respectively. In the USA, the 902 MHz band is used. In order to achieve a long link range, while limiting the transmit power, Sigfox uses Ultra Narrow Band (UNB) radio transmission for both uplink and downlink. The bandwidth of an uplink channel depends on the region , while the downlink channel bandwidth is 1.5 kHz. The maximum uplink transmit power is 25 mW in Europe (158 mW in the USA), whereas the maximum downlink transmit power is 500 mW in Europe (4 W in the USA). The modulations used for the uplink and the downlink are Differential Binary Phase-Shift Keying (DBPSK) and Gaussian Frequency-Shift Keying (GFSK), respectively. DBPSK is more bandwidth-efficient than GFSK, which favors an increased uplink range (compensating for the lower permitted transmit power in the uplink band). In addition, DBPSK yields good protection against interference , as received power then concentrates in a very narrow bandwidth and reaches a high received power level. The uplink physical layer bit rate is 100 bit/s (in Europe) or 600 bit/s (in the United States) whereas the downlink physical layer bit rate is 600 bit/s worldwide.Sigfox uses license-free spectrum, which is subject to spectrum access regulations. For example, in Europe, the bands used by Sigfox for uplink and downlink transmission are subject to a duty cycle limitation of 1% and 10%, respectively . In ordeSigfox defines the physical frame formats for uplink and downlink message transmission see . The minCommunication is asynchronous and device-initiated, which allows the device to stay in sleep state by default and minimize its energy consumption. An uplink message transmission may be received by several base stations , enabliDL_WIN_STARTT, since the end of the first uplink frame transmission, the device initiates a receive window, of maximum duration denoted DL_WIN_MAXT, intended to enable reception of a downlink frame sent by a base station. The downlink frame may carry actual application data for the device and, at the same time, it may also serve as an acknowledgment for the uplink frame. After reception of the downlink message, an uplink confirmation is sent by the device after ACKT time. Note that, in contrast with other technologies, retransmissions due to absence of feedback from the other endpoint of a link do not exist in Sigfox.Sigfox defines two types of message exchanges: unidirectional and bidirectional transactions . In the This section presents models of crucial energy performance parameters of Sigfox, such as device current consumption, device lifetime (for battery-operated devices), and energy efficiency of data delivery. A device periodically transmits an uplink data message  is assumed. The models consider the impact of frame losses. The section is divided in two subsections, which offer the aforementioned models for unidirectional and bidirectional transactions, respectively. All Sigfox physical layer bit rates are considered. avg_uniI. To this end, a profile of the different states involved in a unidirectional transaction is created, considering the duration and current consumption of each state. In order to realistically model the device current consumption characteristics, and without loss of generality, the model is developed based on measurements from a real Sigfox device. We first model the average current consumption of a device communicating by means of undirectional exchanges, denoted The Sigfox device is assumed to periodically perform a transaction, therefore its current consumption behavior is modeled over one period. In this subsection, unidirectional transactions are assumed. Therefore, each period comprises the operations carried out by the device to perform the transmission of one data message, including its replicas, whereas the device is in sleep mode during the remaining time in the period. Note that, in unidirectional transactions, device current consumption is independent of packet losses. Time and current consumption measurement results are obtained from several individual measurements within a transaction period. Negligible differences were found within each set of individual measurements. PeriodT denote the time between two consecutive periodic transactions initiated by the device. Let iT and iI represent the duration and current consumption of state i in avg_uniI, can be obtained as per Equation (1):in indicates the number of times state i is present in the uplink data frame transmission procedure  and states_uniN is 5. Note that sleepT can be computed as:act_uniT denotes the sum of the durations of all states related with transmission activities, i.e., a wake-up state (of duration wuT), 3 transmission states (each one of duration txT), 2 wait next transmission states (of duration wntxT) and the cool down state (of duration cdT):Let txT, is variable and depends on the total uplink frame size (frame_ULl), and on the uplink bit rate in use (ULBR):The transmission time, avg_uniI can be computed by using Equations (1)–(4), the theoretical lifetime of a battery-operated device that performs unidirectional transactions, denoted lifetime_uniT, can be determined as shown next, by taking into account the battery capacity, batteryC (expressed in mA·h), and by approximating a realistic battery behavior by considering the battery self-discharge current, self_disI: self_disI is assumed as a constant value over time. As delivery_uniEC, which indicates the energy consumed by the device per each successfully delivered bit of data payload in unidirectional transactions. delivery_uniEC can be obtained as shown next:V denotes the battery voltage and E[deliveryl] indicates the expected amount of data delivered by the device. In the previous equation, the numerator indicates the energy consumed by the device during PeriodT. The third performance parameter modeled is the energy cost of data delivery, E[deliveryl] depends on the Frame Loss Rate (FLR), and therefore frame losses have an impact on delivery_uniEC. Let Payloadl be the frame payload size, and let ULFLR denote the FLR at the base station for a single uplink frame transmission. The uplink data message will be correctly delivered if at least one of the corresponding three uplink frame transmissions is successfully received. Then, the expected amount of data delivered by the device per transaction is determined as:In unidirectional transactions, the current consumed by the device and its lifetime are independent of uplink frame delivery success. However, avg_biI. The model is derived from measurements on the corresponding current consumption profile of the same hardware platform, and with the same environment and methodology, used in the previous subsection. This subsection models the average current consumption of a device that initiates bidirectional transactions periodically, In a bidirectional transaction, the number of states involved increases compared to that of a unidirectional transaction. The bidirectional transaction starts with the device transmitting the three replicas of its uplink message. Therefore, states 1–3 as described for unidirectional transactions  are alsoavg_biI, can be obtained by using Equations (8) and (9):jT and jI represent the duration and current consumption of state j in jn indicates the number of times state j is present in the uplink data frame transmission procedure . Equations (8) and (9) are equivalent to (1) and (2), however considering now the states described in states_biN , and the time related with bidirectional transaction activities, act_biT. The latter is computed as per the next equation: In the absence of frame losses, the average current, DL_WIN_MAXT. Assuming that all possible downlink start times are equally probable, rxT can be modeled as the expected value of a uniformly distributed random variable within the interval . Therefore, rxT is defined by the following equation:Note that the base station has flexibility to determine the start of a downlink transmission. However, such transmission needs to fit the interval defined by the downlink window, with maximum duration denoted avg_biI is determined in the presence of a non-zero FLR. Three different device current consumption profiles need to be considered, corresponding to three events that may occur, which are denoted A, B and C. Let A be the event where at least one of the three uplink frame transmissions is correctly received by the base station, and the downlink frame is also correctly received by the device. In this case, device current consumption is illustrated by B correspond to the event where the downlink frame is incorrectly received, and therefore the final uplink confirmation is not sent by the device. Finally, let C denote the event where none of the three uplink frame transmissions is correctly received, thus the base station does not send a downlink message, and therefore the device remains listening during the maximum downlink window duration. Based on the three events described, avg_biI can be computed as shown next:AI, BI and CI correspond to the average current consumption over a transaction period where events A, B and C occur, respectively, and Ap, Bp, and Cp denote the corresponding respective probabilities. These current consumption and probability variables can be calculated as described next.Next, AI corresponds to the calculation of avg_biI as determined by using Equations (8)–(11), since both the uplink and the downlink frame transmissions are successful in event A.BI can be obtained similarly to (8), although the states related with sending the uplink confirmation, i.e., states 6 and 7 in B, i.e., the sleep interval in event B, denoted sleep_bi_BT, is calculated by using (14) and (15):CI can be determined on the basis of (13)–(15), but setting rxT to the maximum duration of the downlink receive window, denoted DL_WIN_RX_MAXT, since in event C the device stays in receive mode for that time. Finally, Ap, Bp, and Cp, can be calculated as follows:DLFLR denotes the FLR for downlink transmission. The probabilities lifetime_biT and delivery_biEC denote the device lifetime and the energy cost of data delivery, respectively, for a device that triggers bidirectional transactions. These performance parameters can be obtained on the basis of Equations (5) and (6), by replacing avg_uniI by avg_biI in both equations, as shown next:With regard to the rest of performance parameters considered in this paper, let E[deliveryl], is the same in either a unidirectional transaction or in a bidirectional transaction.Note that the expected amount of data delivered by the device, Based on the models presented in PeriodT values, including values (below 10 min) that are smaller than the minimum ones that stem from the maximum uplink and downlink message rate limitations intended to comply with spectrum access regulations. The purpose is illustrating the performance that can be achieved when such regulations are not in force .The evaluation considers a wide range of PeriodT, for an uplink bit rate of 100 bit/s, FLR = 0, and uplink message payload sizes of 1 byte and 12 bytes. An uplink bit rate of 600 bit/s has also been evaluated; however, for the sake of illustration clarity, the corresponding curve is only shown for a 1-byte payload and unidirectional transactions in PeriodT = 10 min.This subsection evaluates the average Sigfox device current consumption, based on Equations (1)–(4) and (8)–(18). PeriodT = 10 min, unidirectional transactions and a 1-byte payload, the average current consumption is 0.18 mA and 0.11 mA for uplink bit rates of 100 bit/s and 600 bit/s, respectively. The relative impact of the uplink bit rate decreases for bidirectional transactions , and it decreases for both unidirectional and bidirectional transactions as PeriodT increases, where the sleep interval becomes dominant.Impact of the payload size on current consumption is relatively greater for unidirectional transactions, since bidirectional transactions comprise a downlink message and a final uplink confirmation that are independent of the data payload size in the data message sent. Finally, using a 600 bit/s uplink bit rate reduces significantly the current consumption for low to moderate transaction periods, especially for unidirectional transactions. The reason is an uplink frame transmission time decrease by a factor of 6, when compared to using 100 bit/s. For example, for We next evaluate the impact of a non-zero FLR on the current consumption of the device in bidirectional transactions, for an uplink payload size of 1 byte, and an uplink bit rate of 100 bit/s .ULFLR = DLFLR. As shown in B gains non-negligible influence. In this event, the downlink message is lost and the final uplink transmission is not performed, therefore reducing device current consumption . For FLR values greater than 0.5, current consumption increases, since event C  becomes significant. In that event, the uplink transmission is not received by the base station, then there is no downlink message sent in response, and the device stays listening for the whole duration of the downlink receive window. However, in a real deployment, it is expected that FLR values should be reasonably low. Finally, note that the relative impact of FLR on current consumption decreases with the transaction period, since then the sleep interval becomes more dominant. For simplicity, symmetric link performance is assumed, so that On the basis of Equations (5) and (19), and the results presented in the previous subsection, we next determine the device lifetime, for the same range of scenarios considered in the previous subsection. A battery with a capacity of 2400 mAh, and a self-discharge rate of 1%/year of its initial capacity is assumed .PeriodT, for an uplink bit rate of 100 bit/s, for uplink message payload sizes of 1 byte and 12 bytes, and for FLR = 0. An uplink bit rate of 600 bit/s has also been evaluated; however, for the sake of illustration clarity, the corresponding curve is only shown for a 1-byte payload and unidirectional transactions. Overall, device lifetime behavior is inversely proportional to that of current consumption shown in the previous section. As expected, device lifetime increases with the transaction period, with an asymptotic device lifetime of 14.6 years. Differences between the considered options become negligible for a transaction period greater than 1000 min or more, since sleep interval then becomes dominant. Otherwise, differences among the considered options are significant, and they increase (in relative terms) as the transaction period decreases. For example, for a transaction period of 1000 min, and an uplink bit rate of 100 bit/s, device lifetime for unidirectional transactions is 13.4 years and 12.6 years, for 1-byte and 12-byte payloads, respectively. However, for a transaction period of 10 min and the same uplink bit rate of 100 bit/s, device lifetime for unidirectional transactions is 1.47 years and 0.87 years, respectively. As it can be seen, impact of the uplink message payload size on device lifetime is significant, especially for unidirectional transactions, and for low to moderate transaction periods (of up to ~100 min). On the other hand, use of bidirectional transactions significantly reduces device lifetime compared to unidirectional transactions, especially for low to moderate transaction periods. For example, for a 1-byte payload, an uplink bit rate of 100 bit/s and a transaction period of 10 min, device lifetime is 1.47 years and 0.40 years for unidirectional transactions and for bidirectional transactions, respectively. Finally, using an uplink bit rate of 600 bit/s increases device lifetime for low to moderate transaction periods. For example, for PeriodT = 10 min, unidirectional transactions and a 1-byte payload, the device lifetime is 1.47 years and 2.51 years for uplink bit rates of 100 bit/s and 600 bit/s, respectively. Similarly to the behavior of the average current consumption as the transaction period increases, the relative impact of the uplink bit rate decreases for bidirectional transactions , and it decreases for both unidirectional and bidirectional transactions with the transaction period.With regard to non-zero FLR scenarios, the relative impact on device lifetime can be determined on the basis of the results shown in delivery_uniEC and delivery_biEC as a function of the transaction period, for unidirectional and bidirectional transactions, for 1-byte and 12-byte payload sizes, and for uplink bit rates of 100 bit/s and 600 bit/s. For the sake of illustration clarity, from the 600 bit/s uplink bit rate cases, only the curve corresponding to a 1-byte payload and unidirectional transactions is shown. For all considered options, the energy cost of data delivery increases with the transaction period. The reason is that one data payload is delivered per transaction period, and the energy consumption over a transaction period increases with the latter . As the transaction period increases, the difference between using unidirectional and bidirectional transactions becomes less relevant, since the sleep interval becomes dominant. This subsection evaluates the energy cost of data delivery for both unidirectional and bidirectional transaction types, on the basis of Equations (6) and (20). A remarkable result is that, for an uplink bit rate of 100 bit/s, the energy cost of delivering a 12-byte payload with a bidirectional transaction is from 2 to 10 times lower than that of delivering a 1-byte payload with a unidirectional transaction. As expected, the energy cost of data delivery is inversely proportional to the delivered payload size.PeriodT = 10 min, and an uplink bit rate of 100 bit/s, the energy cost of data delivery in unidirectional transactions is 1.59 times greater than that obtained with an uplink rate of 600 bit/s. However, for the same settings but using bidirectional transactions, the relative difference decreases to a factor of 1.06. As the transaction period increases, impact of the bit rate tends to decrease since the active states become less relevant.Finally, the energy cost of data delivery decreases for an uplink bit rate of 600 bit/s, compared to that obtained for an uplink bit rate of 100 bit/s, since transmission time of the uplink messages decreases as well. The quantitative impact of the uplink bit rate is more relevant for unidirectional transactions than for bidirectional ones. For example, for a 1-byte payload, delivery_uniEC and delivery_biEC, delivery_uniEC and delivery_biEC increase by up to 52% and 64%, respectively, when compared to FLR = 0.In order to better assess the impact of loss rate on both This subsection studies the impact of critical parameters, such as the sleep current, the Sigfox device transmit power, and the uplink frame size, on the model presented in this paper.sleepI. As discussed in sleepI settings such as 16 µA and 1 µA, for different transaction types, and FLR = 0. An uplink bit rate of 100 bit/s is assumed. As it can be seen, impact of sleepI increases with the transaction period, since sleepI is the asymptotic current consumption value . For bidirectional transactions, and a 12-byte payload, the sleepI settings considered lead to significant current consumption differences for a PeriodT of around 100 min or greater. For unidirectional transactions, and a 1-byte payload, current consumption differences arise for lower PeriodT values , due to the lower overall current consumption in unidirectional transactions.A parameter with a crucial impact on energy consumption metrics is the sleep current, txI depends on the transmit power setting.Another parameter that is relevant in terms of energy consumption is the Sigfox device transmit power. The device used in our evaluation only supports one transmit power value . Such a value matches the maximum allowed device transmit power according to EU regulations, and for this reason it is commonly used as the default or the only transmit power setting in other Sigfox hardware platforms ,10,11,13txI values, such as the one obtained with our measurements, i.e., 27.6 mA, and 15 mA, different transaction types and uplink payload sizes. An uplink bit rate of 100 bit/s is assumed. As shown in txI, is relevant for low transaction periods. The impact of txI is greater for unidirectional transactions, since in bidirectional transactions the Sigfox device consumes a significant amount of current during the receive window. Finally, another relevant parameter is the uplink frame size. Note that this parameter grows linearly with the uplink frame payload size and, as already illustrated in FLR > 0.5), and a non-zero FLR increases the energy cost of data delivery.As shown in While using a battery as the energy source for a sensor device is a common approach, energy harvesting is also a relevant alternative. This section evaluates the minimum feasible transaction period for a Sigfox device powered by an energy harvesting source. The results are obtained based on Equations (1)–(4) and (8)–(18), considering 1-byte and 12-byte payloads, unidirectional and bidirectional transactions, and two energy harvesting system models: a Panasonic AT-7665A film outdoor solar panel, and a Panasonic AM-1815CA glass indoor solar panel ,24. The PeriodT values considered in this paper, i.e., it does not limit by itself the minimum feasible PeriodT. However, the indoor panel supplies a much lower current (three orders of magnitude below the outdoor panel one). This requires accumulating the energy harvested by the indoor panel over relatively large periods of time before allowing completing a transaction, up to ~1.5 h or ~4 h for unidirectional and bidirectional transactions, respectively.This paper has presented analytical models that allow to evaluate the current consumption and the lifetime of a battery-enabled Sigfox device, as well as the energy cost of data delivery. The model, which has been derived based on measurements performed on real hardware, captures the impact of using uplink and downlink communication, the frame payload size, the uplink bit rate, and frame losses on the aforementioned energy performance parameters.The average current consumption decreases with the transaction period, with an asymptotic value equal to the sleep state current consumption. Differences among the considered options decrease as well with the transaction period. For low transaction periods, bidirectional communication increases current consumption by a factor up to ~4. Current consumption is only affected by frame losses for bidirectional transactions. In those, since an uplink frame is sent thrice, the impact of frame losses becomes only relevant for very high FLR values, where the device awaits a downlink frame for the maximum receive window duration. Assuming a 2400 mAh battery, and the device model used in the study, the theoretical asymptotic device lifetime is 14.6 years. Similarly to the observations made for current consumption, differences between using bidirectional or unidirectional transactions are significant for low transaction periods. For an uplink bit rate of 100 bit/s, a 1-byte payload and a transaction period of 10 minutes, device lifetime is 1.49 years and 0.40 years for unidirectional transactions and for bidirectional transactions, respectively. Using an uplink bit rate of 600 bit/s (in regions where that is possible) increases device lifetime for low to moderate transaction periods. For a transaction period of 10 min, unidirectional transactions and a 1-byte payload, the device lifetime is 1.49 years and 2.57 years for uplink bit rates of 100 bit/s and 600 bit/s, respectively.The uplink frame payload size has a greater impact on the energy cost of data delivery than on the rest of performance parameters considered. Increasing the uplink frame payload size amortizes the energy consumed per delivered bit by a factor similar to the payload size increase. Using an uplink bit rate of 600 bit/s leads to remarkable energy cost savings (up to a factor of 1.84). Frame losses impact on the energy cost for rather high FLR values (of 0.5 or greater) for both unidirectional and bidirectional transactions, to a greater extent for the latter.sleepI and txI, two relevant parameters. Finally, energy harvesting sources have been considered as well, illustrating that powerful ones allow the operation of the Sigfox device for the whole range of transaction types and periods considered in this paper, whereas more limited energy harvesting sources constrain the range of feasible transaction periods.The paper also evaluates the sensitivity of the current consumption model to


According to the United Nations, males and females should be given equal treatment in physical and psychological services, and healthcare institutions should exert greater efforts to reduce the gap in gender equality. However, this issue has been largely ignored in previous literature on healthcare environments. Designing a hospital environment that focuses on gender differences is critical to academic researchers and practical managers in all healthcare institutions. Thus, as an exploratory effort, this study aims to develop a measurement to assess customer perceptions of gender-friendly hospital environments. To identify and refine the structure of the instrument, two studies are conducted at different hospitals in Taiwan. The exploratory evidence shows there are five factors  and 28 items in the measurement scale of gender-friendly hospital environments. Results also show that gender-friendly hospital environments affect customers’ loyalty and willingness to pay. Based on our findings, hospital practitioners and researchers can adopt the measurement instrument used in this study to deal with the gap of gender equality in healthcare environments. A healthcare physical environment is a place where patients with health conditions go for treatment . The quaHealthcare patients have more options to choose from in a competitive market. Patients often make comparisons with other healthcare providers, and they are becoming increasingly aware of their central role in the type of healthcare they purchase . CustomeThe rest of this paper is structured as follows: Traditional healthcare environment designs considered only the visions of architects, construction engineers, and administrators. This lack of customer-centered design has led many hospitals to build healthcare environments that primarily focus on efficiency and clinical functionality . A reseaThe concept of gender mainstreaming, as proposed by the United Nations, has been widely discussed in the last decades. Mainstreaming involves ensuring that gender perspectives with the aim of gender equality are central in all research, legislations, and policies in the entire United Nations system. In hospital service environments, gender equity objectives have been identified in the position statements of the World Health Organization (WHO). The policy of gender equity is to reduce the health gaps between males and females, and enhance gender equality in health systems and healthcare services. Researchers have pointed out the differences between the healthcare service processes of men and women ,19. DoyaCombining the concept of gender differences with hospital environment design is a good strategy to enhance the quality of hospital healthcare services and increase gender equality in health systems and healthcare services ,22. FromSeveral studies have investigated the impact of the quality of a hospital’s environment on patient outcomes, including health recovery, hospital perception, satisfaction, and overall well-being . ArneillEliminating gender disparities is an important issue that has been proposed by the United Nations. According to the WHO, reducing the gap in gender equality should be addressed in all healthcare institutions. Accordingly, the concept of gender-friendliness in hospital environments deals with the differences between male and female patients ,19. HealFrom the lack of literature on gender-friendly hospital environments, we have drawn theoretical foundations from literature on environmental psychology and marketing. Stimulus-organism-response (S-O-R) theory is an appropriate framework to interpret the influences of gender-friendly hospital environments on patient outcomes. The S-O-R model is an extension of the classic stimuli-response theory that integrates the role of an organism into the link between stimuli and response. The theory posits that environmental cues (stimuli) influence an individual’s internal evaluation (organism), which further produces behavioral outcomes (response) ,29. WhenHypothesis 1.Gender-friendly hospital environments will be positively related to customer loyalty.Hypothesis 2.Gender-friendly hospital environments will be positively related to customer willingness to pay.The purpose of Study 1 is to identify the constructs of the measurement scale of gender-friendly hospital environments. Initial items for gender-friendly hospital environments were generated from two sources. First, we selected key words regarding gender differences based on a literature review of hospital environment quality and environmental psychology ,32,33,34p < 0.001). This finding indicates an acceptable level of factorability for the factor analysis. Furthermore, a total of five factors were identified with an eigenvalue greater than unity, which cumulatively explains 79.51% of the variance. All factor loadings of items on each factor were greater than 0.5, except one item with cross loadings. A detailed look at the factor loadings of these five factors indicates that the first factor of gender-friendly hospital environments consisted of five items that measured the surrounding physical environments of a hospital—thus, it was named “physical design”. The second factor consisted of seven items  that measured the space and functional design of a hospital and was thus named “functional design”. The third factor consisted of five items that measured the physical signs, symbols, and image design of a hospital and was thus named “marking design”. The fourth factor consisted of eight items that measured the awareness and attitude of a hospital on gender-friendly issues; thus, it was named “gender perception”. The final factor consisted of three items that measured the gender-friendly service quality of a hospital and was thus named “gender-friendly services”. The average loading of the 28 items on their respective factors of gender-friendly hospital environments was 0.75. The internal consistency reliability for physical design, functional design, marking design, gender perception, and gender-friendly services were 0.94, 0.95, 0.92, 0.95, and 0.91, respectively. These results indicate good reliability of the measurement scale. Therefore, the final constructs and items for the measurement of gender-friendly hospital environments consisted of five factors with 28 items, as shown in To determine the factorial structure of the measurement scale of gender-friendly hospital environments, an EFA was applied using a maximum likelihood method with a varimax rotation. According to the EFA method, the threshold values of factor loadings for the items are greater or equal to 0.5, and Cronbach’s coefficient alpha for multi-item measures are acceptable at 0.6 or above ,36,37. TAlthough the results of Study 1 show the constructs and items for the measurement scale of gender-friendly hospital environments, stronger evidence may be needed to assure the structure of the instrument. The purpose of Study 2 is to refine the measurement scale generated in Study 1 and test the hypotheses of this study. A formal survey was conducted in hospitals in central Taiwan in 2017. In this study, the survey questionnaire included 28 items from the measurement generated in Study 1, and 10 items assessing the loyalty and willingness to pay of customers. Participants were asked to complete the structured questionnaire with a five-point Likert-type scale ranging from 1 (strongly disagree) to 5 (strongly agree). A final sample of 300 questionnaires were returned, of which 249 were valid, resulting in a response rate of 83%. Twenty-eight items from the five factors of the measurement scale generated in Study 1 were used in Study 2. Physical design was measured with five items, functional design was measured with seven items, marking design was measured with five items, gender perception was measured with eight items, and gender-friendly services were measured with three items.Customer loyalty is defined as a deeply held commitment to re-purchase a preferred product or service repetitively from the same brand, despite external influent factors to cause switching behavior . To measWillingness to pay is a measure of the value that a customer assigns to his/her consumption in monetary units. It is defined as the amount of money or price a customer is willing to pay for a product or service . In the Several demographic characteristics of the respondents were controlled in our analysis. Gender was coded with a dummy variable, where 0 indicates female and 1 indicates male; education was measured using five categories ; age was measured based on seven categories ; and monthly income was measured using five categories , 1 = NT$30,000–below NT$40,000, 2 = NT$40,000–below NT$50,000, 3 = NT$50,000–below NT$60,000, and 4 = NT$60,000 or above).p < 0.001). This result indicates an acceptable level of factorability for the factor analysis. It likewise shows that seven factors were identified with an eigenvalue greater than unity, and these seven factors cumulatively explained a total of 79.35% of the variance. All factor loadings of items on each factor were greater than 0.5. Customer loyalty consisted of six items, customer willingness to pay consisted of four items, and the remaining five factors represented the five dimensions of gender-friendly hospital environments. The first factor of gender-friendly hospital environments was physical design, which consisted of five items; the second factor was functional design, which had seven items; the third factor was marking design, which consisted of five items; the fourth factor was gender perception, which consisted of eight items; and the final factor was gender-friendly services, which consisted of three items. The average loading of the 28 items on their respective factors of a gender-friendly hospital environment was 0.69, and cross loadings were negligible. The values of internal consistency reliability for customer loyalty, customer willingness to pay, physical design, functional design, marking design, gender perception, and gender-friendly services were 0.95, 0.83, 0.93, 0.95, 0.94, 0.96, and 0.92, respectively. These results indicate good reliability of the measurement scale. The results of the EFA are shown in To refine the factorial structure of the measurement scale of gender-friendly hospital environments, an EFA was also applied in Study 2 by using a maximum likelihood method with a varimax rotation. The results of the EFA are presented in Podsakoff, MacKenzie, and Lee  suggester = 0.32, p < 0.01; functional design: r = 0.41, p < 0.01; marking design: r = 0.44, p < 0.01; gender perception: r = 0.35, p < 0.01; and gender-friendly services: r = 0.38, p < 0.01). In addition, the five dimensions of gender-friendly hospital environments were significantly and positively correlated to customer willingness to pay . Regression analysis was used to test the hypotheses in the next section.p < 0.001), functional design was significantly and positively related to customer loyalty , marking design was significantly and positively related to customer loyalty , gender perception was significantly and positively related to customer loyalty , and gender-friendly services were significantly and positively related to customer loyalty . The overall results of the construct of gender-friendly hospital environments show that they were significantly and positively related to customer loyalty . Thus, Hypothesis 1 was supported.p < 0.001), functional design was significantly and positively related to customer willingness to pay , marking design was significantly and positively related to customer willingness to pay , gender perception was significantly and positively related to customer willingness to pay , and gender-friendly services were significantly and positively related to customer willingness to pay . The overall results of the construct of gender-friendly hospital environments show that they were significantly and positively related to customer willingness to pay . Thus, Hypothesis 2 was also supported.The purpose of this study was to develop an instrument to measure customer perceptions on gender-friendly hospital environments. As an exploratory effort, the results of Study 1 identified five factors, with 28 items in the instrument of gender-friendly hospital environments. The results of Study 2 refined the measurement scale and showed that the instrument consisted of five factors with 28 items, namely, physical design with five items, functional design with seven items, marking design with five items, gender perception with eight items, and gender-friendly services with three items. The empirical results of Study 2 also indicated the positive impacts of gender-friendly hospitals on customers’ loyalty and willingness to pay. The findings of this study provide important implications for academic researchers and practical managers.From a research perspective, healthcare environment design is an important component in the healthcare quality system. In recent years, researchers have focused their attentions on customer-centered design; however, the role of gender differences has not been discussed in previous literature on healthcare environment design. This study integrated the concept of gender differences in hospital environment design, and thus contributes to the knowledge in the field of healthcare environments. In addition, it plays an important role as a first effort in developing an instrument for gender-friendly hospital environments, thus providing insights for understanding the critical role of gender differences and helping increase gender equality in health systems and healthcare services.From a managerial perspective, based on the findings of this study, architects, designers, and planers can take advantage of a measurement that assesses the perceptions of customers on the quality of the healthcare environment. Hospitals should make changes toward customized services that consider gender differences as the main attributes in designing healthcare environments. In particular, hospitals should stress the attributes of physical environments, functionality, and marking designs, and these attributes should fit well with the demands of males and females. Furthermore, with respect to the social environment, hospitals should emphasize the importance of gender perceptions, as well as gender-friendly services. The findings of this study show that gender-friendly hospital environments have a positive influence on patient outcomes. This result provides implications for hospital administrators and managers in planning service strategies that reduce gender differences and enhance gender equality in hospital healthcare services. Such strategies reflect the needs and expectations of individual customers, thus increasing the customers’ loyalty and willingness to pay.In summary, the attempt to develop an instrument for gender-friendly hospital environments in this study is the first important step in the research on healthcare environment design. This preliminary foundation contributes to the literature on hospital quality. This study also provides implications for hospital architects, designers, administrators, and managers in improving hospital service quality and enhancing the quality of health and well-being of customers.Although this study has been designed meticulously, some limitations that should be addressed in future research are acknowledged. First, this study only identified and refined the factorial structure and items of the measurement scale of gender-friendly hospital environments. As an exploratory study, the validity of the instrument has not been tested in this study. Thus, additional evidence on the validity of the measurement instrument should be examined and confirmed in future research. Second, the measurement items were developed based on Taiwanese respondents and are thus only suitable for hospital environments in Taiwan. Future research can rely on our measurement instrument to examine the issue of gender-friendly hospital environments in other contexts. Third, the study deals only with two variables of customer outcomes, namely, loyalty and willingness to pay. Other possible outcome variables can include customer satisfaction, word of mouth, trust, and quality of healthcare treatment. These variables should be further examined in future research. Finally, patients are believed to be more sensitive to hospital environment designs regarding gender differences, because they are the central focus of the healthcare process. Thus, the measurement scale of this study was developed primarily to assess customer perceptions. Future research can consider the experiences of hospital staff members and the evaluations of hospital designers in designing the measurement instrument of gender-friendly hospital environments.