| Summary: | Financial incentives for health have recently received increasing attention, but are subject to ethical concerns surrounding their fairness and coerciveness. Monetary Contingency Contracts (MCCs), which require individuals to deposit money, refunded contingent on reaching a goal, are a potential alternative strategy. This thesis aimed to explore the utility of MCCs in the treatment of overweight and obesity. Firstly, a review evaluated systematically the evidence for weight loss-based MCCs. Findings indicated a significant small-to-medium effect of MCCs on both weight loss and participant retention during treatment, but no significant effects post-treatment. Several intervention characteristics were associated with greater weight loss (group refunds; deposit paid in instalments; participant-set deposit size; use of additional behaviour change techniques) and greater retention (deposit paid as one lump sum; researcher-set deposit size; refunds delivered on an all or nothing basis; refunds contingent on attendance at classes). The findings also revealed that little evidence is available on certain types of MCCs such as those in which refunds are contingent on both the weight loss of an individual and a weight loss partner (pair-based MCCs). In studies 1 (N=56) and 2 (N=14), questionnaires and semi-structured interviews provided an indication of the likely engagement with and acceptability of various types of MCCs for overweight and obese individuals in the UK. In study 1, participants showed a reluctance to pay into pair-based MCCs. Study 2 suggested this stemmed from fear of lack of partner reciprocation, but that emphasising the usefulness of partner contact may encourage participation. Finally, a pilot study was conducted to explore the feasibility and efficacy of a weight loss intervention employing pair-based MCCs. Pair-based MCCs were significantly more effective in reducing adiposity (but not weight loss) compared to individual MCCs or a comparison condition. Findings will contribute to the evidence base for the feasibility and utility of administering weight loss-based MCCs in the UK.
|
|---|
