The dynamics of decision-making in weight loss and maintenance: a qualitative enquiry

Behavioural approaches to weight loss are often initially successful but less so in the longer term, as some people maintain the necessary behaviour changes while others do not. This study aimed to derive possible explanations for this using a qualitative approach with a view to improving intervention effectiveness.

Thirty-six participants in a development and feasibility study for a weight loss and maintenance intervention (called SkiM) were interviewed three times over 18 months regarding their experiences before, during and after the intervention. Data were analysed thematically. The accounts of those who were more and less successful in terms of longer term weight loss were compared, and a conceptual model linking the main analytic themes was developed.

Five interpretative themes were generated: encountering and managing key situations; the impact of emotion; the source of control; personal values; and acquiring knowledge and skills. These themes were linked through a model of decision-making during key situations. In this model, behavioural decisions emerge from a dynamic interplay between several drivers: emotional state and needs, perceived control, personal values, the individual's knowledge and skills, and their existing habits. The individual's response in key situations generates experiential learning that can influence decisional dynamics in similar situations in future. These dynamics appeared to differ between participants, and between those who were more and less successful in weight management.

Our analysis and model of decision-making during weight-management have implications for the development and delivery of behavioural weight management interventions. By helping individuals to identify the drivers of their decision-making in key situations, and equipping them to manage these drivers, programmes may enhance their capacity to sustain the behaviour changes needed for long-term weight loss.