Promoting dietary behaviour change in low socioeconomic status groups

Abstract

Living in deprived areas is associated with poorer health and higher rates of obesity and overweight. Tackling such health inequities is complex as health behaviours are influenced by an interplay between environmental, psychological and biological factors. Furthermore, a dearth of knowledge around barriers to behaviour change in low socioeconomic populations exists, including evidence around how to improve adherence to lifestyle interventions. Key research questions identified were 1) What are the barriers and facilitators to weight loss/lifestyle behaviour change for adults living in low socioeconomic areas? 2) Are commitment devices effective in improving adherence to lifestyle interventions? 3) Is a commitment based intervention feasible to deliver within this population? These were addressed through a series of four studies. The first qualitative study aimed to identify the challenges and facilitators to lifestyle behaviour change in low socioeconomic areas within the context of weight loss groups. Observations of the weight loss groups preceded semi-structured interviews with group facilitators (n=11) and service users (n=14), and data were analysed using thematic analysis. The second study was a systematic review and meta-analysis to identify the utility of commitment devices (e.g. commitments, contracts, and pledges) for improving adherence to, and outcomes from lifestyle interventions. The third study developed an intervention (SMART-C) using findings from the first two studies, alongside stakeholder involvement and the wider literature, guided by the Behaviour Change Wheel. The aim was to design an intervention to enhance weight loss groups delivered within low socioeconomic areas, with the aim of improving dietary behaviour change. The final mixed methods study aimed to refine the intervention through assessing its feasibility in six weight loss groups, with a focus on acceptability and engagement. Qualitative data consisted of interviews with facilitators (n=4) and service users (n=12), quantitative data consisted of questionnaires (n=28) and intervention engagement data. Data were analysed using the Theoretical Framework of Acceptability. From the first study, barriers to lifestyle behaviour change were identified at the individual and group levels (lack of knowledge, language and literacy barriers, cultural diversity, focus on service engagement rather than outcomes) and social and environmental levels (cost, access and availability, complex social situations). Results suggested a need to tailor interventions for this population, by identifying ways to engage both service providers and users with behaviour change techniques rather than reliance upon information provision. Findings from the systematic review suggest that commitment devices (primarily behavioural contracts) show some promise as components of lifestyle (dietary) interventions for weight loss outcomes in the short (mean difference 1.5 kg, 95% CI: 0.7, 2.4) and possibly longer term (mean difference 1.7kg; 95% CI: 0.0, 3.4). However, the evidence base is small (10 studies), and of relatively poor quality, suggesting further evidence is required. The intervention focused on the in-group behaviour of goal setting and active review, which was previously lacking. Using the COM-B model and Theoretical Domains Framework to guide the behavioural diagnosis, changes were required to Psychological Capability, Physical Opportunity, Reflective Motivation and Social Opportunity. The result was a six-week dietary goal setting and contracting booklet targeting dietary behaviours (SMART-C), which was an add-on tool to be used in the context of a community weight loss group. The final study established that the intervention is acceptable to all users, suggesting it is easy to use and deliver, content is suitable and coherent with existing groups, and perceived as effective. Suggested changes to further refine SMART-C include the addition of physical activity goals, and some flexibility around number of goals selected. Further training for intervention deliverers may improve intervention fidelity with regards to goal review. Results suggest that reporting engagement data alongside acceptability data may enhance understanding of an interventions' use. The studies add to our understanding of behaviour change in low SES communities by revealing that commitment devices are an acceptable, feasible, and potentially effective addition to support weight loss in this community. Future research should determine SMART-C's effectiveness within this setting, and further feasibility studies are required to determine its transferability to other contexts.

Date of Award	2 Apr 2020
Original language	English
Awarding Institution	The University of Manchester
Supervisor	Sarah Peters (Supervisor) & Sarah Cotterill (Supervisor)