Psychosocial environment: definitions, measures and associations with weight status a systematic review

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1 doi: /obr Supplement Article Psychosocial environment: s, s and associations with status a systematic review K. Glonti 1, J. D. Mackenbach 2,J.Ng 3, J. Lakerveld 2, J.-M. Oppert 4,5, H. Bárdos 6, M. McKee 1 and H. Rutter 1 1 ECOHOST The Centre for Health and Social Change, London School of Hygiene and Tropical Medicine, London, UK; 2 Department of Epidemiology and Biostatistics, EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands; 3 Department of Service Planning and Care Integration, Sengkang Health, Singapore; 4 Equipe de Recherche en Epidémiologie Nutritionnelle (EREN), Centre de Recherche en Epidémiologie et Statistiques, Inserm (U1153), Inra (U1125), Cnam, COMUE Sorbonne Paris Cité, Université Paris 13, Bobigny, France; 5 Sorbonne Universités, Université Pierre et Marie Curie, Université Paris 06; Institute of Cardiometabolism and Nutrition, Department of Nutrition, Pitié-Salpêtrière Hospital, Assistance Publique-Hôpitaux de Paris, Paris, France; 6 Department of Preventive Medicine, Faculty of Public Health, University of Debrecen, Debrecen, Hungary Summary Socio-ecological models suggest that many elements of the social environment act as upstream determinants of obesity. This systematic review examined s, s and strength of associations between the psychosocial environment and adult status. Studies were included if they were conducted on adults, the outcome was status, carried out in any developed country and investigated at least one psychosocial environmental construct. Six databases for primary studies were searched: EMBASE, MEDLINE, PsycINFO, Scopus, Web of Science and the Cochrane Library. We restricted our search to studies published in English between January 1995 and February An adapted Quality Assessment Tool for Quantitative Studies was used to evaluate risk of bias of included studies. Out of 14,784 screened records, 42 articles were assessed using full text. A total of 19 studies were included. The strongest associations with status were found for social capital and collective efficacy, although few studies found significant associations. There was heterogeneity in the s and metrics of psychosocial environmental constructs. There is limited evidence that greater social capital and collective efficacy are associated with healthier status. The research conducted to date has not robustly identified relations. We highlight challenges to undertaking research and establishing causality in this field and provide recommendations for further research. Received 16 December 2015; revised 17 December 2015; accepted 18 December 2015 Address for correspondence: K. Glonti, ECOHOST The Centre for Health and Social Change, 104, London School of Hygiene and Tropical Medicine, Tavistock Place, London WC1H 9SH, UK. ketevan.glonti@lshtm.ac.uk Keywords:, psychosocial environment, social capital, SPOTLIGHT Abbreviations: BMI, body mass index. obesity reviews (2016) 17 (Suppl. 1), Background is a worldwide public health concern, with increasing obesity rates, particularly in high income countries (1). Poor diets, physical inactivity and sedentary behaviour are major drivers of obesity, and frameworks such as the ANalysis Grid for Environments Linked to (ANGELO) have been designed in an effort to conceptualize and understand factors operating at various levels that drive the obesity pandemic through these behaviours (2). These 2016 World 81

2 82 Psychosocial environment and obesity K. Glonti et al. obesity reviews suggest that there is a dynamic relation between individuals and their broader social environment. Although there is no universally agreed, social environment has been broadly defined as the environment that influences an individual s behaviour through promoting a sense of social control through the creation of social norms (3). It encompasses social determinants of health that can potentially be altered (4). Social environment can be grouped into five dimensions social support and social networks, socioeconomic status and income inequality, racial discrimination, social cohesion and social capital and neighbourhood deprivation (5). A 2011 systematic review of the influence of built environments on cardio-metabolic risk factors, including obesity, found the strongest associations with community socioeconomic factors, while aspects of social interactions were rarely investigated (6). Two systematic reviews linking obesity to socioeconomic status have been published (6,7), but the remaining social constructs that gained prominence in epidemiological research on status and obesity have not yet been summarized. These remaining constructs are of a psychosocial nature and include social cohesion (8), collective efficacy (9), social capital (10), social support and social networks (11). The social environment includes the communities to which individuals belong and the policies created to provide order to their lives and varies across contexts and settings (11). Our aim was systematically to review and evaluate evidence on associations or lack of them between psychosocial environment and status in adults. We also summarize the s and ment approaches used to explore relations between the psychosocial environment and status and provide recommendations for future research. By understanding the role of the psychosocial environment in status, potential targets for policies to prevent increasing obesity may be identified. This review was conducted as part of a European-funded project (SPOTLIGHT) addressing the social and environmental determinants of obesity (12). Methods The review included published primary research that investigated the association between social environmental constructs and status in adults (aged 18 years). Six electronic databases: EMBASE, Global Health, MEDLINE, PsycINFO, Scopus, Web of Science and the Cochrane Library were searched in February Reference lists of all included papers were searched for articles that had not been identified in the electronic searches. We restricted our search to studies published in English between January 1995 and 15 February A full description of search terms and search strategy can be found in Supporting Information 1. Studies were included if they were conducted on adult populations; the outcome was status; investigated at least one psychosocial environmental construct; were not focused solely on socioeconomic status; presented original research and were carried out in any developed country, i.e. classified as very high human development by the Human Development Index of the United Nations Development Programme. We adhered to an adapted version of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) (13), to conduct this review and report its findings (Supporting Information 2). Study screening and selection Following removal of duplicates, two reviewers (J. D. M. and K. G.) independently screened search results by title and abstract. Full texts of potentially suitable articles were obtained and reviewed for inclusion by both reviewers. Disagreements were resolved by discussion and consensus. Data extraction and analysis Data from each study on country, study design, s used, analyses performed and key findings were extracted for a narrative synthesis. Substantial differences in variables, methods, data and context limited direct comparison and rendered a statistical meta-analysis of the findings difficult. For this reason, we did not extract the effect sizes and p-values presented in the original studies. Risk of bias assessment We used an adapted version of the Quality Assessment Tool for Quantitative Studies (as developed by the Effective Public Health Practice Project) (14) that has been used in this way before (15) to assess the risk of bias of the included studies. The tool contains 19 items within eight key domains. As some of these relate only to specific study designs, each paper received a score accordingly. Studies can have between six and eight ratings, with each component score ranging from 1 (low risk-of-bias; high methodological quality) to 3 (high risk-of-bias; low methodological quality). An overall rating for each study was determined based on its component rating. Further details can be found in Supporting Information 2. The study assessments were completed by two independent reviewers (J. D. M. and J. N.). The ratings for each of the eight domains, as well as the total rating, were compared, and consensus was reached on a final rating for each included article. Results The results of the screening process are described using an adapted Preferred Reporting Items for Systematic Reviews and Meta-Analyses flowchart (Fig. 1) (13). In total, 2016 World

3 Psychosocial environment and obesity K. Glonti et al. 83 Figure 1 Preferred Reporting Items for Systematic Reviews and Meta-Analyses flowchart. 14,784 articles were screened by title and abstract for inclusion. The full text of 42 articles was obtained and assessed for eligibility. Although a total of 20 studies met the eligibility criteria for this review, only 19 were included because two papers referred to the same study with overlapping results (16,17). We included the 2011 study by Prince et al. (17) rather than the later one by the same group because of its more comprehensive description of methods and results. The studies were conducted in Australia (18,19), Canada (17,20,21), Portugal (22), the UK (23) and the (24--35). Eighteen studies used a cross-sectional and one a longitudinal design. Full details are provided in Table 1. Risk of bias assessment Thirteen studies had a low risk of bias, with the remaining six studies having a moderate risk of bias. Full details of all ratings are provided in Supporting Information 3. Seven studies (17,20,24,25,32,33,35) were rated as strong and 12 as moderate (18,19,21--23,26--31,34) for representativeness. All studies with the exception of four moderate ones (19,28,30,35) received a strong rating for avoidance of confounding. Eight studies scored strong (21,23,25,27,30--33) on data collection, nine scored moderate (17,19,21,22,24,26,28,29,35) and two scored weak (18,20) as they did not provide any information about the validity and reliability of their s. With the exception of one (31), all studies received a strong rating for the robustness of their data analysis. Seventeen studies showed high quality of reporting and received strong ratings, while the remaining two achieved moderate (23,24) scores in reporting quality. Definitions and constructs of psychosocial environment In the included studies, the authors distinguished between five psychosocial environmental constructs; two studies examined collective efficacy, five social cohesion, ten social capital and five social support. These s and the applications of these constructs across the included studies are summarized later. Collective efficacy Bjornstrom investigated whether local income inequality was associated with an increased likelihood of obesity and whether collective efficacy mediated the relation (24). The author refers to the of Sampson et al. of collective efficacy as a community social resource that captures the extent to which residents share norms, trust one another and are willing to intervene for the common good (36). Burdette et al. used the same and examined the hypothesis that mothers of young children would have a higher prevalence of obesity if they lived in a neighbourhood that they perceived as having a low level of collective efficacy (28) World

4 84 Psychosocial environment and obesity K. Glonti et al. obesity reviews Table 1 Description of the studies on associations between psychosocial environment and status Source Country Study design Analysis Social environmental construct and level Spatial scale Weight Associations with status Quality rating Ball and Crawford, 2006 (19) Australia Bivariate and multiple linear Social support as individuallevel National level (urban, rural and remote areas) Social support for healthy diets from family, and sabotage to healthy diets and physical activity from friends, significantly predicted women s current BMI, with higher levels of support and lower levels of sabotage associated with higher BMI Moderate (2) Bjornstrom, 2011 (24) Logistic models Collective efficacy as Census tracts Collective efficacy does not mediate the relationship between inequality and obesity. It is associated with a decrease in the odds of obesity Burdette 2006 (28) One way ANOVA andgeneral linear models Collective efficacy as Census tracts from d and/or selfreported No significant association between collective efficacy and either BMI or obesity Moderate (2) Christian 2011 (18) Australia Multiple linear and social cohesion as New housing development No of obesity No significant association between BMI and social capital or social cohesion Moderate (2) Greiner, 2004 (25) Multivariable logistic Community social capital as Participants were asked about their community No statistically significant association between obesity and community ratings or community involvement Holtgrave and Crosby, 2006 (33) Linear model as state-level State level correlated moderately with obesity, shown to have a protective effect against obesity Kaplan, 2003 (21) Canada Longitudinal Multivariate logistic Social support as individuallevel State level Social support was associated with a lower likelihood of obesity for women and higher likelihood of obesity for men (Continues) 2016 World

5 Psychosocial environment and obesity K. Glonti et al. 85 Table 1 (Continued) Source Country Study design Analysis Social environmental construct and level Spatial scale Weight Associations with status Quality rating Keller 2013 (31) Bivariate correlations Social cohesion and social support as individual-level Postcode sectors Waist-to-hip ratio body composition from d and height No of obesity No statistically significant associations between BMI and social cohesion or social support Kendzor 2013 (34) Latent variable modelling Social support as individuallevel Houston metropolitan area from d and height Social support was inversely associated with negative effect and positively associated with BMI Kim 2006 (35) Two-level analyses and threelevel analyses as state-level and countylevel State and county had modest protective effects on obesity Moore 2013 (29) Paired t-tests, Spearman rank correlations, ANOVA and two-level mixed Social cohesion as Census tracts No of obesity Point estimates of associations revealed that higher social cohesion was associated with lower BMI for both the home and workplace environments, although associations were not statistically significant for home environment and social cohesion Mujahid 2008 (26) Marginal maximum likelihood estimation Social cohesion as 1 mile area around home for non- MESA participants from d and height No of obesity No statistically significant association between BMI and social cohesion in women. Statistically significant associations were present for men who had higher social cohesion; they had a higher mean BMI. Poortinga, 2006 (23) UK Multilevel logistic and social support as Postcode sectors from d and height Trust is associated with a decrease in the odds of obesity. Powell- Wiley 2013 (27) Multivariable logistic Social cohesion as PHDCN-CS s (not specified), participants were asked about their neighbourhood Waist circumference from d and height Definition of obesity No statistically significant association between obesity and social cohesion (Continues) 2016 World

6 86 Psychosocial environment and obesity K. Glonti et al. obesity reviews Table 1 (Continued) Source Country Study design Analysis Social environmental construct and level Spatial scale Weight Associations with status Quality rating Prince 2011 (17) Canada Multilevel multivariable logistic Natural barriers (e.g. rivers), spatial scale ments and individuallevel data Definition of obesity ( 25 kg/m 2 ) In men, stronger neighbourhood sense of community belonging was significantly associated with being physically active, and lower neighbourhood SES and higher voting rates were significantly associated with lower odds for over and obesity. Santana 2009 (22) Portugal Multilevel logistic Administrative boundaries of wards Definition of over and obesity ( 25 kg/m 2 ) No statistically significant association between social capital and over Moderate (2) Sullivan 2014 (30) Proc surveylogistic procedures Logistic No Participants were asked about their neighbourhood. Definition of obesity The odds of obesity were significantly lower for adults who reported involvement in clubs, associations or help groups Moderate (2) Veenstra 2005 (20) Canada Multivariable logistic Census tract level, sociodemographic data and GIS to identify neighbourhoods Definition of over ( 27 kg/m 2 ) Depth and breadth of involvement in voluntary associations significantly related to over status. More involvement in networks of associations corresponded with a lower likelihood of being over. Moderate (2) Yoon and Brown, 2011 (32) Multilevel linear models Community social capital 288 counties Definition of obesity Greater CSC on average appears to increase the likelihood of eating fewer calories or less fat to reduce or maintain. BMI, body mass index; CSC, Community social capital; GIS, geographic information system; MESA, Multi-Ethnic Study of Atherosclerosis; PHDCN-CS, Project on Human Development in Chicago Neighborhoods Community Survey; SES, socioeconomic status. Social cohesion Five studies examined social cohesion (18,26,27,29,31). Two looked at associations between perception of neighbourhood physical and social environments and status (26,27); however, neither specified an overall of social cohesion, instead referring to s that have been used as indicators or proxies of social cohesion. Thus, both Mujahid et al. and Powell-Wiley et al. included willingness to help neighbours and people trusted as indicators of social cohesion. In addition, Mujahid et al. included sharing similar values and getting along with each other (26), whereas Powell-Wiley et al. included reporting a close-knit neighbourhood as a constituent element of social cohesion (27). Christian et al. examined whether the individual, behavioural, social and built environments were correlated with body mass index (BMI). The authors did not define social cohesion but referred to the neighbourhood cohesion scale (37). Moore et al. evaluated how residential and work environments may separately and jointly relate to BMI, referring to the 2016 World

7 Psychosocial environment and obesity K. Glonti et al. 87 of social cohesion proposed by Sampson et al. (36). Finally, Keller et al. analysed relations between social support, neighbourhood environment factors and body composition among postpartum Latinas in the. The authors do not explicitly define social cohesion (31). A further 10 studies focused on social capital (17,18,20,22,23,25,30,32,33,35). The aim of the exploratory study by Holtgrave and Crosby was to examine the relation between social capital and obesity and diabetes in the adult population in the. The authors conceptualized social capital as a combination of trust, reciprocity and cooperation among members of a social network, referencing work by Kawachi et al. and Putnam (33). Prince et al. examined the relation between variables related to the built and social environments and physical activity and over/obesity. Civic participation and trust, as well as sense of belonging, were used as indicators of social capital (17). The authors referred to the construct of Kawachi et al. of social capital (10), described as elements of community organization such as civic participation and sense of trust between citizens that contribute to the mutual benefit of the community. Poortinga examined the associations of perceived social capital with people s physical activity, BMI and general health (23), also drawing on the construct of Kawachi et al. of social capital (10). Greiner et al. examined the relation between community social capital and health outcomes that included obesity. The authors broadly subscribe to Putnam s (38) of social capital as the resources available to individuals and communities through their social connections (25). Yoon et al. also refer to Putman s, focusing on the structural component of community social capital, manifest as community-level resources such as density of social networks that facilitate cooperative actions for mutual benefit among members of a community (32). Kim et al. explored the relations between social capital d at the US state and county levels and individual leisure-time physical inactivity (35). The authors broadly refer to social capital as the resources embedded in social structures that are accessed and/or mobilized in purposive action (39) and also refer to Putnam s state-level social capital index (40). Christian et al. also explored, but did not define, social capital. Elements of social capital included satisfaction with number of friends, number of people known and whether the participants neighbourhood was perceived as a good place to live and raise children (18). Veenstra et al. explored the association between involvement in voluntary associations and BMI, describing social capital in terms of the depth and breadth of involvement in voluntary organizations, with reference to Berkman et al. (20,41). Santana et al. examined the contribution of the local environment (both physical and social) and personal attributes to the risk of gain and obesity (22). Although the authors referred to the concept of bonding social capital, they did not explicitly define it, although in the literature on social capital, it is normally used to describe links between individuals within the same group, as distinct from bridging social capital, which describes links between individuals of different groups (42). Bonding social capital was assessed at neighbourhood level using variables such as the number of recreational or sport clubs, number of local newspapers and the local newspaper circulation per inhabitant (22). Sullivan et al. examined possible associations between perceived neighbourhood environments and obesity. The authors provided neither of social capital nor a reference to a social capital construct but used participation in clubs, associations and groups in neighbourhood as a proxy indicator for social capital (30). Poortinga s study investigated the links between perceived aspects of the social and physical environment, physical activity obesity and selfrated health. The author provided no particular for social capital but defined it through social trust and civic participation (23). Social support Five studies examined social support (19,21,23,31,34). Ball and Crawford explored the biological, psychological, social and environmental correlates of young women s current and retrospective 2-year change. The authors made no reference to any particular of social support but refer to it as social support from family/friends for physical activity and healthy eating behaviours (19). Kaplan et al. examined the factors associated with over and obesity among older men and women. They provide no of social support but reference previous work (43), stating that their encompasses major distinct dimensions of social support such as instrumental, informational, appraisal and emotional support (21). Kendzor et al. evaluated a previously tested model of the psychosocial pathways through which socioeconomic status might influence BMI. One of the hypothesized psychosocial mediators is social support. The authors do not provide a of social support or any reference to a particular concept (34). Keller et al. analysed relations between social support, neighbourhood environmental factors and body composition among postpartum Latinas in the. The authors do not define social support or social cohesion (31). Finally, Poortinga provided no particular for social support but used the social support scale and grouping from the 1987 Health and Lifestyle Survey (23,44). Measures of the psychosocial environment There was great heterogeneity across studies with regard to the constructs and s of the psychosocial environmental factors. Full details are provided in Table World

8 88 Psychosocial environment and obesity K. Glonti et al. obesity reviews Table 2 Psychosocial environment constructs and s Source Constructs Measures Ball and Crawford, 2006 (19) Bjornstorm, 2011 (24) Burdette 2006 (28) Christian 2011 (18) Greiner 2004 (25) Social support: from family/friends for physical activity and healthy eating behaviours Collective efficacy: social cohesion, trust and propensity for collective action Collective efficacy: social cohesion and trust and informal social control : satisfaction with number of friends, number of people known, if neighbourhood is a good place to live and raise children Social cohesion: belonging, loyalty, helping each other, collective action and shared values Community social capital: approximation to trust and social participation Social support as individual-level assessed by four subscales. These comprised two sets (family/friends) of 18 questions, adapted from Sallis et al. The four subscales were as follows (1) support for healthy eating (six items: e.g. how often have family, partner, children, parents complimented me on my eating habits); (2) sabotage of healthy eating (three items: e.g. offered me high fat or unhealthy foods); (3) support for physical activity (six items: e.g. participated in physical activity with me); and (4) sabotage of physical activity (three items: e.g. suggest things that are physically inactive). Collective efficacy as a neighbourhood-level composed aggregated responses to 10 items that capture social cohesion, trust and propensity for collective action:(1) This is a close-knit neighbourhood ; (2) Adults in this neighbourhood watch out for children ; (3) There are adults in this neighbourhood kids can look up to ; (4) People in this neighbourhood can be trusted ; (5) People generally don t get along with each other ; (6) Residents are willing to help their neighbours ; (7) Residents do not share the same values ; (8) Neighbourhood children were skipping school and hanging out on a street corner ; (9) Spraypainting graffiti on a local building ; and (10) Showing disrespect. Collective efficacy as a neighbourhood-level composed of aggregated responses to 10 items that capture social cohesion, trust and propensity for collective action: (1) This is a close-knit neighbourhood ; (2) Adults in this neighbourhood watch out for children ; (3) There are adults in this neighbourhood kids can look up to ; (4) People in this neighbourhood can be trusted ; (5) People generally don t get along with each other ; (6) Residents are willing to help their neighbours ; (7) Residents do not share the same values ; (8) Neighbourhood children were skipping school and hanging out on a street corner ; (9) Spraypainting graffiti on a local building ; and (10) Showing disrespect. as a neighbourhood-level composed of aggregated responses to five items measuring neighbourliness. Social cohesion as a neighbourhood-level composed of aggregated responses to 18-item neighbourhood cohesion scale (1) Overall, I am attracted to living in this neighbourhood; (2) I feel like I belong to this neighbourhood; (3) I visit my friends in their homes; (4) The friendships and associations I have with other people in my neighbourhood mean a lot to me; (5) Given the opportunity, I would like to move out of this neighbourhood; (6) If I need advice about something I could go to someone in my neighbourhood; (7) I believe my neighbours would help in an emergency; (8) I borrow things and exchange favours with my neighbours; (9) I would be willing to work together with others on something to improve my neighbourhood; (10) I plan to remain a resident of this neighbourhood for a number of years; (11) I like to think of myself as similar to the people who live in this neighbourhood; (12) I rarely have a neighbour over to my house to visit; (13) I regularly stop and talk with people in my neighbourhood; (14) Living in this neighbourhood gives me a sense of community; (15) Overall I think this is a good place to bring up children; (16) If the people in my neighbourhood were planning something, I d think of it as something we were doing rather than they were doing; (17) I think I agree with most people in my neighbourhood about what is important in life; and (18) I feel loyal to the people in my neighbourhood. Authors refer to community social capital but divide the concept into two questions that community rating/trust (How would you rate your community as a place to live?) and social participation (During the past 5 years, have you been active in a coalition or civic group which attempted to address one or more community problems?), which are reviewed separately as county-level s composed of aggregated responses. (Continues) 2016 World

9 Psychosocial environment and obesity K. Glonti et al. 89 Table 2 (Continued) Source Constructs Measures Holtgrave and Crosby, 2006 (33) Kaplan 2003 (21) Keller 2013 (31) Kendzor 2013 (34) Kim 2006 (35) Mujahid 2008 (26) Poortinga, 2006 (23) Powell-Wiley 2013 (27) Prince 2011 (17) Santana 2009 (22) : trust, reciprocity and cooperation among members of a social network Social support: instrumental, informational, appraisal and emotional Social cohesion: willing to help neighbours, trust-worthiness, share same value and getting along with each other Social support: for exercise and general Social support: tangible support, belonging and appraisal Social cohesion: willing to help neighbours, trustworthiness, share same value and getting along with each other : social trust and civic participationsocial support: rating the physical and emotional support obtained from family and friends under various scenarios Social cohesion: willingness to help neighbours, close-knit neighbourhood and people trusted : civic participation and trust Sense of belonging to community : number of recreational or sport clubs, number of local newspapers and local newspaper circulation per inhabitant as a state-level composed of aggregated responses to a combination of 14 variables that span the domains of community organizational life, involvement in public affairs, volunteerism, informal sociability and social trust. Social support as individual-level assessed with four items that reflected whether the respondents felt that they had someone they could confide in, count on, give them advice and make them feel loved and cared for. The total social support score was derived from the sum of all affirmative responses (yes vs. no) to the four items. The items tap on major distinct dimensions of social support such as instrumental, informational, appraisal and emotional. Social cohesion and social support as individual-level. Social cohesion (four items): (1) Willing to help neighbours, (2) Trustworthiness, (3) Share same values, and (4) Getting along with each other.social support for exercise (PA): adapted 9-item version of Social Support and Exercise Survey assessing frequency of engagement and participation of family members and friends in PA Social support as individual-level.the ISEL-12 is a 12-item self-report of perceived availability of social support that contains three subscales. The Tangible Support subscale s the perceived availability of material aid (e.g. able to borrow money if needed), the Belonging subscale s the perceived availability of others with whom one may engage in activities, and the Appraisal subscale s the perceived availability of others with whom one can talk about problems. Items are rated on a 4-point scale, and scores may range from 4 to 16 on each subscale. Higher scores indicate greater social support. as a state and county level composed of aggregated responses to two state-level social capital scales from 10 indicators and two county-level scales from five indicators Social cohesion as neighbourhood-level assessed by social environment score that combined s of aesthetic quality (five items), walking environment (seven items), availability of healthy foods (three items), safety (three items), violent crime (four items) and four items for social cohesion: (1) Willing to help neighbours (2) Trustworthiness, (3) Share same values, and (4) Getting along with each other. and social support as neighbourhood-level.social capital: two items from HSE questionnaire1 Generally speaking, would you say that most people can be trusted? Or you can t be too careful in dealing with people. Civic participation was d by asking respondents to indicate whether they regularly join in activities of 14 types of clubs or associationssocial support: summation of responses to seven statements and subsequent categorization into three groups from the 1987 Health and Lifestyle Survey Social cohesion as neighbourhood-level assessed through three items from PHDCN-CS questionnaire: (1) Willingness to help neighbours, (2) Close-knit neighbourhood, and (3) People trusted and sense of belonging to community as.: d by proxy using 2006 voting ratessense of belonging to community: one item from CCHS questionnaire: How would you describe your sense of belonging to your community? as neighbourhood-level. Quantification by researchers observation (Continues) 2016 World

10 90 Psychosocial environment and obesity K. Glonti et al. obesity reviews Table 2 (Continued) Source Constructs Measures Sullivan 2014 (30) Veenstra 2005 (20) Yoon and Brown, 2011 (32) : civic participation : depth and breadth of involvement in voluntary organizations Community social capital as neighbourhood-level. d by proxy using participation in block clubs, associations and help groups in neighbourhood as neighbourhood-level. Three items in researcher-created questionnaire(1) Please tell me the name of any group or voluntary organization you belong to (2) How involved are you in the activities and affairs of this group or organization you belong to? (very involved, somewhat involved, not very involved, not at all involved) (3) Is there any other group or voluntary organization you belong to? Community social capital as community-level. Ratio of full-time employees in voluntary organizations to population (PSCI). Seventeen out of 18 categories of voluntary organizations were applied here. Only the category any group which meets over the internet could not be matched. CCHS, Canadian Community Health Survey; HSE, Health Survey for England; ISEL-12, Interpersonal Support Evaluation List; MOS-SS, Medical Outcomes Study: Social Support Scale; PA, physical activity; PHDCN-CS, Project on Human Development in Chicago Neighborhoods Community Survey; PSCI, Petris Social Capital Index. Collective efficacy In accordance with the construct of Sampson Bjornstrom (24) and Burdette et al. (28) examined collective efficacy as a neighbourhood-level composed of aggregated responses to items that capture trust, social cohesion and the willingness to intervene for the common good among residents. Social cohesion The five studies that examined social cohesion all differed in the s used. Mujahid et al. assessed social cohesion as assessed by a social environment score that combined items in four dimensions (greater aesthetic quality, safety, less violent crime and social cohesion) in a factor analysis. Social cohesion was d using four items based on research by Diez-Roux (26). Powell-Wiley et al. conceived social cohesion as a neighbourhood-level (27). It is assessed through three items abstracted from questions on neighbourhood perception used in the 1994 Project on Human Development in Chicago Neighbourhoods Community Survey (36). Christian et al. d social cohesion at neighbourhood-level using an 18-item neighbourhood cohesion scale (18,45). Moore et al. examined social cohesion as neighbourhood-level assessed with four items based on the 5-item Sampson Scale (36) but indicate in their article that they are using four items to assess social cohesion without further specification (29). Finally, Keller et al. d social cohesion as an individual-level, comprising four items measuring willing to help neighbours, trustworthiness, share same value and getting along with each other (31). Different approaches to measuring social capital were used in ten studies. Holtgrave and Crosby used state-level correlational analyses. The of social capital was obtained from Putnam s public use data set (40). The is a combination of 14 variables that span the domains of community organizational life, involvement in public affairs, volunteerism, informal sociability and social trust (33). Prince et al. assessed social capital as neighbourhood-level by proxy, using voter turnout in the 2006 Ottawa municipal election and by aggregating self-reported neighbourhood values using a single item repeated over four cycles of the Canadian Community Health Survey to generate a of sense of community belonging (17). Poortinga examined social capital as a neighbourhood-level. Social trust and civic participation were used as indicators of social capital (46), d using two questions from the 2003 Health Survey for England (23). Greiner et al. used two constructs: community rating and social participation to approximate the trust and social participation items employed in a prior study by Goodman et al. (47) as structural indicators of social capital, although they are d separately, not as a score (25). The of Yoon et al. of community social capital is the Petris Social Capital Index (PSCI). The PSCI is a geographically based proxy for community social capital and is calculated from the County Business Patterns and population data from the US Census Bureau and represents a ratio of total employees in voluntary organizations. The PSCI is based on membership of voluntary organizations, one of the social capital s collected by the Social Capital Community Benchmark Survey. In the Social Capital Community Benchmark Survey, there are 18 different categories of voluntary organizations. The authors were able to match all of them with the exception of anygroupwhichmeets over the internet (32). Kim et al. d social capital at the US state and county level. Two state-level social 2016 World

11 Psychosocial environment and obesity K. Glonti et al. 91 capital scales were derived from 10 indicators and two county-level scales from five indicators (35). Christian et al. assessed social capital as a neighbourhood-level comprising aggregated responses to five items measuring neighbourliness (45). Veenstra et al. d social capital as a neighbourhood using two items on involvement in voluntary associations/organizations (26). Santana et al. assessed social capital as a neighbourhood-level. The authors d bonding social capital by the number of local recreational/sports associations and number of local newspapers as well as the local newspaper circulation per inhabitant (22). Sullivan et al. assessed social capital as by proxy using participation in block clubs, associations and help groups in neighbourhood (30). Social support Ball and Crawford d social support as an individual-level for -related behaviour with eight subscales. These comprised two sets (family/friends) of 18 questions, adapted from Sallis et al. (48). Kaplan et al. d social support as an individual-level assessed using four items that captured whether the respondents felt that they had someone they could confide in, count on, give them advice or make them feel loved and cared for. The total social support score was derived from the sum of all affirmative responses to the four items (21). Kendzor et al. assessed social support as an individual-level. The authors used the Interpersonal Support Evaluation List to assess social support on three different levels: (1) Tangible Support measuring the perceived availability of material aid; (2) Belonging measuring the perceived availability of others to engage in activities; and (3) Appraisal perceived availability of others with whom one can talk about problems (34). Keller et al. d social support as an individual-level. They distinguish between social support for exercise (adapted 9-item version of Social Support and Exercise Survey), assessing frequency of engagement and participation of family members and friends in physical activity, and general social support (19-item Medical Outcomes Study) using the Social Support Scale (31). Poortinga examined social support as a neighbourhood-level, a summation of responses to seven statements and subsequent categorization into three groups from the 1987 Health and Lifestyle Survey (44). Associations between psychosocial environment and obesity All studies used BMI to define status, with Powell- Wiley et al. (27) and Moore et al. (29) using waist circumference as an additional. However, discrepancies in the of status were noted. Four studies (18,26,29,31) did not report their of obesity, despite using change in BMI as an outcome and drawing links between obesity and social determinants in their findings. Eleven studies (19,21,23--25,27,28,30,32--34) defined obesity as a BMI 30 kg/m 2 (2), consistent with World Health Organization guidelines (1). The remaining three studies either combined both obese and over BMI status in their reporting (17) or focused primarily on over individuals (20,22), using a BMI cut-off of 25 kg/m 2 (2) as per World Health Organization guidelines. One study (20) defined over as having a BMI 27 kg/m 2 (2). A number of associations between constructs of the psychosocial environment and status were identified as detailed below. Collective efficacy From the two studies on collective efficacy, only Bjornstrom found that increased levels are associated with a decrease in the odds of obesity. The analysis was interpreted as showing that it exerted an independent and beneficial effect on obesity but did not mediate the relation between inequality and obesity (24). Social cohesion From the five studies on social cohesion, three found significant associations with obesity. Mujahid et al. found no significant association between neighbourhood social environment and BMI in women, although men with higher social environment scores had a higher mean BMI. This was also the case when social cohesion was investigated separately men with higher social cohesion had a higher mean BMI (26). Prince et al. found that the social environment had no impact on female physical activity or over/obesity status. However in males, a stronger neighbourhood sense of community belonging was significantly associated with being physically active, whereas lower neighbourhood socioeconomic status and higher voting rates were significantly associated with lower odds of over and obesity (17). Finally, Moore et al. found that in general, point estimates of associations revealed that higher social cohesion was associated with lower BMI for both the home and workplace environments, although associations were not statistically significant for home environment and social cohesion (29). Eight studies examined social capital, and five significant associations were found. Holtgrave and Crosby found that social capital correlated moderately with obesity. It was shown to have a protective effect against obesity (33). Prince et al. found that higher social capital in men was significantly associated with lower odds of being over or obese (17). Sullivan et al. found that adults who reported that they were involved in neighbourhood clubs, associations or support groups had significantly decreased odds of 2016 World

12 92 Psychosocial environment and obesity K. Glonti et al. obesity reviews obesity. However, race/ethnicity appeared to modify these associations. After further stratification by race/ethnicity, report of involvement in neighbourhood clubs, associations or support groups was only significantly associated with a decreased odds of obesity among non-hispanic Caucasian adults (30). Yoon et al. found that greater community social capital on average appears to increase the likelihood of eating fewer calories or less fat to reduce or maintain (32). Kim et al. found that social capital had modest protective effects on obesity (35). In Poortinga s study, only trust appeared to be significantly associated with obesity; people with a high level of trust were 14% less likely to be obese than people with a low level of trust (23). Social support From the five studies on social support, four found significant associations. Ball and Crawford found that perceived social support for healthy diets from family, and sabotage to healthy diets and physical activity from friends, significantly predicted women s current BMI, with higher levels of support and lower levels of sabotage associated with higher BMI (19). Kaplan et al. found that social support was associated with a lower likelihood of obesity for women and a higher likelihood of obesity for men (21). Veenstra et al. found that depth and breadth of involvement in voluntary associations were significantly related to over. Greater involvement corresponded to a lower likelihood of being over (20). Kendzor et al. found that social support was inversely associated with negative affect and positively associated with BMI (34). Discussion We systematically reviewed literature on associations between psychosocial environmental factors and status in adults. We found 19 relevant articles with few significant associations between the psychosocial environment and obesity, which indicates that the currently available evidence for such associations is weak. A total of 22 associations on psychosocial environment and status were examined in 19 studies resulting in 13 significant associations. One was consistent with the hypothesis that collective efficacy is related to adult obesity. From the five studies on social cohesion, three found significant associations. Eight studies examined social capital, and five significant associations were found. From the five studies on social support, four found significant associations. There was a great heterogeneity in the s and s used, which limited the comparability of study results. Social environment is a construct that encompasses many different dimensions, so it is not surprising that attempts to simplify it to a single dimension fail to adequately capture the richness of the concept and are unable to demonstrate the complex associations. We identified three main possible explanations for a lack of consistent associations: psychosocial environmental factors were not well defined; the design of included studies did not allow for detection of meaningful associations, or there was absence of association between psychosocial environmental factors and status. The studies identified in this review lacked robust and consistent conceptual frameworks, clear s and distinct constructs. Similar findings were identified in a recent systematic review on obesity interventions targeting psychosocial environmental factors (49), which suggests that these constructs used in adult obesity research are still at an early stage of development. In the studies included in this review, the authors distinguished between four different constructs, but it is unclear how distinct they actually are. is the most popular construct, and most of the social capital s tended to draw on the work of Putnam (38) and Coleman (50). Krishna et al. refer to social capital as being divided into structural and cognitive components; what people do (voting and attending church) and what people feel (trust and friendship) (51). This suggests that collective efficacy and social support should be part of the cognitive construct of social capital. On the other hand, Edwards et al. suggest that trust is not a part of social capital, but rather a factor that predisposes to social capital (52). Social constructs are complex, so simple proxies are unlikely to capture their complexity (53). Yet such proxies are often all that are available in the large surveys that have also considered over and/or obesity. For all social constructs, it is important to distinguish between individual and collective characteristics (54). The mechanisms linking social capital or related constructs to obesity may be dependent on the level at which the social factors are d. In this review, we incorporated studies that d social capital of individuals on different levels. However, none of the studies in this review studied the contextual effects of psychosocial environmental factors, which may be important given the evidence that the influence of micro-level s of social capital on health vary according to characteristics of the country such as civil liberties and the scale of the informal economy (55). Only a few studies related neighbourhood-level social s (e.g. neighbourhoods with high and low social capital) to individual-level obesity. This kind of analysis would be needed to detect any neighbourhood-level (contextual) effect of social environmental factors. Psychosocial constructs depend on specific physical contexts and settings (56), but the ment approaches in all these studies are based on spatial aggregation of individual responses from surveys at neighbourhood level (57). In contrast, more recent instruments designed to capture the 2016 World

13 Psychosocial environment and obesity K. Glonti et al. 93 influence of the physical environment on health combine both objective s at community level and aggregate perceptions (58). If the construct d at neighbourhood level actually operates at a higher level of aggregation, such as city or state, it is not possible to identify meaningful links. As noted earlier, there is a distinction between bonding and bridging social constructs; bonding capital refers to social cohesion within a group, while bridging capital refers to social cohesion across different groups (59). When studying social capital within neighbourhoods, it is important to consider the particular nature of neighbourhood social capital in order to avoid drawing false conclusions about the level at which this social construct acts. A better understanding of the interactions between psychosocial factors and obesity-related behaviours could provide useful support for environmental policy actions to tackle obesity. However, the evidence base in this review is predominantly of North American origin, with resulting limitations in terms of its applicability to European countries. A particularly serious limitation is the unavoidable predominance of cross-sectional studies, which makes the direction of association between psychosocial factors and status impossible to determine. Additionally, the findings in this paper highlight the lack of consistent s, ments and strong associations of psychosocial environmental factors and obesity. In the light of this methodological deficit in the research, it is currently challenging to provide any substantial policy recommendations. Any knowledge translation into the broader policy context will require stronger studies. Strengths and limitations of the review The study is a novel attempt to explore s, s and associations between the psychosocial environment and obesity. We performed an extensive literature search but only found a small number of studies that met our inclusion criteria. This may be due to the language restriction (English language articles only) as well as the focus only on the adult population, thus excluding studies of children and adolescent (60,61). By limiting our review in this way, we could assess the s and s used critically and in detail. We used the limiter humans only for our search. While the application of this limit can help to reduce the number of hits, it might also miss results that may have been misclassified in the databases. We assessed the risk of bias of the included articles. Although the quality tool indicates that the studies were of moderate to strong quality, it seems that they were not particularly strong on some items that were not assessed that may be of importance in this type of research, particularly the use of clear s and conceptual foundations. We acknowledge that the adapted quality tool used has some limitations, but it is based on recommendations from a number of authors (62--65) and is commonly used in obesity research. Definitions and conceptual foundations are difficult to capture in tools for quantitative studies and may require qualitative interpretation by the researchers. Conclusions Research conducted to date on psychosocial constructs has not robustly identified significant relations with status in adults. Clearer s and ments are needed, as well as further longitudinal research to identify mechanisms through which social environments exert their effects on status in adults. Researchers who look into these constructs must collectively reach consensus positions on s and frameworks. This review shows that policy recommendations may be premature as the current evidence is inconclusive. Declaration of interests The authors have no conflicts of interest to declare. Acknowledgements The SPOTLIGHT project was funded by the Seventh Framework Programme (CORDIS FP7) of the European Commission, HEALTH (FP7-HEALTH-2011-two-stage), grant agreement no The content of this article reflects only the authors views, and the European Commission is not liable for any use that may be made of the information contained therein. Supporting information Additional supporting information may be found in the online version of this article, Supplement 1. Search terms and search strategy Supplement 2. Quality assessment tool Supplement 3. Quality assessment ratings References 1. World Health Organization. : preventing and managing the global epidemic. World Health Organization technical report series Swinburn B, Egger G, Raza F. Dissecting obesogenic environments: the development and application of a framework for identifying and prioritizing environmental interventions for obesity. Prev Med 1999; 29: Institute of Medicine. The Future of the Public s Health in the 21st Century. National Academies Press, Krieger N. A glossary for social epidemiology. J Epidemiol Community Health 2001; 55: World