Systematic prevention of overweight and obesity in adults: a qualitative and quantitative literature analysis

To date, most interventions aimed at preventing obesity have underemphasized the application of systematic intervention development, implementation and evaluation. The present review provides a thorough insight in factors promoting implementation and/or effectiveness in interventions aimed at preventing overweight/obesity among adults. A total of 46 studies evaluating interventions aimed at preventing obesity were reviewed, followed by both qualitative and quantitative analyses. The Intervention Mapping protocol and the Environmental Research framework for weight Gain prevention (EnRG) were applied to analyse and classify the included studies. The interventions were categorized by setting (workplace, community, health care) and target group (ethnic minorities, pregnant women, [pre]menopausal women, smokers, people with intellectual disabilities). Generally, interventions were found to have potential in changing energy balance-related behaviours and anthropometric outcomes. Effect sizes for changes in body mass index ranged between -0.09 and 0.45. When the programme goal specifically aimed at weight management, the intervention was found to be more successful than interventions with programme goals that were aimed at preventing cardiovascular disease or improving general health status. Although a considerable part of studies included motivational interventions, only some actually assessed the effects on potential cognitive mediators. A general lack of reporting underlying theoretical models for behaviour change was observed as well as the inclusion of linkage groups and strategies to promote empowerment.