Environmental changes aimed at encouraging walking or cycling may promote activity and improve health, but evidence suggests small or inconsistent effects in practice. Understanding how an intervention works might help explain the effects observed and provide guidance about generalisability. We therefore aimed to review the literature on the effects of this type of intervention and to understand how and why these may or may not be effective. We searched eight electronic databases for existing systematic reviews and mined these for evaluative studies of physical environmental changes and assessed changes in walking, cycling or physical activity. We then searched for related sources including quantitative or qualitative studies, policy documents or reports. We extracted information on the evidence for effects ('estimation'), contexts and mechanisms ('explanation') and assessed credibility, and synthesised material narratively. We identified 13 evaluations of interventions specifically targeting walking and cycling and used 46 related sources. 70% (n = 9 evaluations) scored 3 or less on the credibility criteria for effectiveness. 6 reported significant positive effects, but higher quality evaluations were more likely to report positive effects. Only two studies provided rich evidence of mechanisms. We identified three common resources that interventions provide to promote walking and cycling: (i) improving accessibility and connectivity; (ii) improving traffic and personal safety; and (iii) improving the experience of walking and cycling. The most effective interventions appeared to target accessibility and safety in both supportive and unsupportive contexts. Although the evidence base was relatively limited, we were able to understand the role of context in the success of interventions. Researchers and policy makers should consider the context and mechanisms which might operate before evaluating and implementing interventions.

Modifying transport infrastructure to support active travel (walking and cycling) could help to increase population levels of physical activity. However, there is limited evidence for the effects of interventions in this field, and to the best of our knowledge no study has convincingly demonstrated an increase in physical activity directly attributable to this type of intervention. We have therefore taken the opportunity presented by a 'natural experiment' in Cambridgeshire, UK to establish a quasi-experimental study of the effects of a major transport infrastructural intervention on travel behaviour, physical activity and related wider health impacts. The Commuting and Health in Cambridge study comprises three main elements: a cohort study of adults who travel to work in Cambridge, using repeated postal questionnaires and basic objective measurement of physical activity using accelerometers; in-depth quantitative studies of physical activity energy expenditure, travel and movement patterns and estimated carbon emissions using household travel diaries, combined heart rate and movement sensors and global positioning system (GPS) receivers; and a longitudinal qualitative interview study to elucidate participants' attitudes, experiences and practices and to understand how environmental and social factors interact to influence travel behaviour, for whom and in what circumstances. The impacts of a specific intervention - the opening of the Cambridgeshire Guided Busway - and of other changes in the physical environment will be examined using a controlled quasi-experimental design within the overall cohort dataset. Addressing the unresolved research and policy questions in this area is not straightforward. The challenges include those of effectively combining different disciplinary perspectives on the research problems, developing common methodological ground in measurement and evaluation, implementing robust quantitative measurement of travel and physical activity behaviour in an unpredictable 'natural experiment' setting, defining exposure to the intervention, defining controls, and conceptualising an appropriate longitudinal analytical strategy.

The proportion of obese women is nearly twice the proportion of obese men in Barbados, and physical inactivity may be a partial determinant. Using qualitative interviews and ‘semi-structured’ participant observation, the aim of this study was to identify modifiable barriers to physical activity and to explore the factors that facilitate physical activity amongst overweight and obese women in this low-resourced setting. Seventeen women aged 25 to 35 years with a BMI ≥25, purposefully sampled from a population-based cross-sectional study conducted in Barbados, were recruited in 2014 to participate in in-depth semi-structured interviews. Twelve of these women participated in one or more additional participant observation sessions in which the researcher joined and observed a routine activity chosen by the participant. More than 50 hours of participant observation data collection were accumulated and documented in field notes. Thematic content analysis was performed on transcribed interviews and field notes using the software Dedoose. Social, structural and individual barriers to physical activity were identified. Social factors related to gender norms and expectations. Women tended to be active with their female friends rather than partners or male peers, and reported peer support but also alienation. Being active also competed with family responsibilities and expectations. Structural barriers included few opportunities for active commuting, limited indoor space for exercise in the home, and low perceived access to convenient and affordable exercise classes. Several successful strategies associated with sustained activity were observed, including walking and highly social, low-cost exercise groups. Individual barriers related to healthy living strategies included perceptions about chronic disease and viewing physical activity as a possible strategy for desired weight loss but less effective than dieting. It is important to understand why women face barriers to physical activity, particularly in low-resourced settings, and to investigate how this could be addressed. This study highlights the role that gender norms and health beliefs play in shaping experiences of physical activity. In addition, structural barriers reflect a mix of resource-scarce and resource-rich factors which are likely to be seen in a wide variety of developing contexts.

Diabetes related foot disease is a major cause of morbidity and mortality in people with diabetes. This is despite the fact that interventions to reduce the burden of diabetic foot disease are estimated to be highly cost effective, even cost saving in both developed and developing countries. This exploratory qualitative study was undertaken in a developing country known to have a very high rate of diabetes related amputations. The aim of the study was to explore barriers to foot care from the perspectives of health care professionals and patients, with a view to informing further work to develop effective interventions. Semi-structured interviews, each of 30 to 60 minutes, were conducted with a purposive sample of 20 individuals (11 health carers and 9 patients with diabetes). Participants were asked how diabetic foot care was experienced and practised, and about knowledge and attitudes relevant to care. Health carers were also asked how they negotiated issues of priority setting within the available resources. Interviews were recorded, transcribed and underwent thematic analysis. Three broad categories of potential barriers to diabetic foot care were identified. First, health carers reported that they and their patients tended to prioritise glycaemic control and that this often eclipsed foot care. Second, health carers described resistance to changing professional roles, particularly within the context of limited resources. Newly assigned foot screening and care duties did not fit in easily with their main work schedule. The overall effect of this was to lead to increased referrals to already overstretched, and difficult to access, podiatrists. Finally, patients reported a health care system with significant reliance on ‘self-care’ ability, including the need for time and expertise to negotiate access to scarce professional foot care appointments. The findings from this exploratory study provide insight on broad barriers to diabetic foot care within a developing country setting. The three areas identified deserve further investigation to determine their impact on the delivery of diabetic foot care and the implications for designing effective interventions.

Approaches to synthesising qualitative data have, to date, largely focused on integrating the findings from published reports. However, developments in text mining software offer the potential for efficient analysis of large pooled primary qualitative datasets. This case study aimed to: a) provide a step‐by‐step guide to using one software application, Leximancer; and b) interrogate opportunities and limitations of the software for qualitative data synthesis. We applied Leximancer v4.5 to a pool of five qualitative, UK‐based studies on transportation such as walking, cycling and driving, and displayed the findings of the automated content analysis as inter‐topic distance maps. Leximancer enabled us to ‘zoom out' to familiarise ourselves with, and gain a broad perspective of, the pooled data. It indicated which studies clustered around dominant topics such as ‘people'. The software also enabled us to ‘zoom in' to narrow the perspective to specific sub‐groups and lines of enquiry. For example, ‘people' featured in men's and women's narratives but were talked about differently, with men mentioning ‘kids' and ‘old', whereas women mentioned ‘things' and ‘stuff'. The approach provided us with a fresh lens for the initial inductive step in the analysis process, and could guide further exploration. The limitations of using Leximancer were the substantial data preparation time involved, and the contextual knowledge required from the researcher to turn lines of inquiry into meaningful insights. In summary, Leximancer is a useful tool for contributing to qualitative data synthesis, facilitating comprehensive and transparent data coding but can only inform, not replace, researcher‐led interpretive work.

Diabetes (DM) is estimated to affect 10–15% of the adult population in the Caribbean. Preventive efforts require population wide measures to address its social determinants. We undertook a systematic review to determine current knowledge about the social distribution of diabetes, its risk factors and major complications in the Caribbean. This paper describes our findings on the distribution by gender. We searched Medline, Embase and five databases through the Virtual Health Library, for Caribbean studies published between 2007 and 2013 that described the distribution by gender for: known risk factors for Type 2 DM, prevalence of DM, and DM control or complications. PRISMA guidance on reporting systematic reviews on health equity was followed. Only quantitative studies (n>50) were included; each was assessed for risk of bias. Meta-analyses were performed, where appropriate, on studies with a low or medium risk of bias, using random effects models. We found 50 articles from 27 studies, yielding 118 relationships between gender and the outcomes. Women were more likely to have DM, obesity, be less physically active but less likely to smoke. In meta-analyses of good quality population-based studies odds ratios for women vs. men for DM, obesity and smoking were: 1.65 (95% CI 1.43, 1.91), 3.10 (2.43, 3.94), and 0.24 (0.17, 0.34). Three studies found men more likely to have better glycaemic control but only one achieved statistical significance. Female gender is a determinant of DM prevalence in the Caribbean. In the vast majority of world regions women are at a similar or lower risk of type 2 diabetes than men, even when obesity is higher in women. Caribbean female excess of diabetes may be due to a much greater excess of risk factors in women, especially obesity. These findings have major implications for preventive policies and research.