Cost-effectiveness of habit-based advice for weight control versus usual care in general practice in the Ten Top Tips (10TT) trial: economic evaluation based on a randomised controlled trial

Abstract

ObjectiveTen Top Tips (10TT) is a primary care-led behavioural intervention which aims to help adults reduce and manage their weight by following 10 weight loss tips. The intervention promotes habit formation to encourage long-term behavioural changes. The aim of this study was to estimate the cost-effectiveness of 10TT in general practice from the perspective of the UK National Health Service.DesignAn economic evaluation was conducted alongside an individually randomised controlled trial.Setting14 general practitioner practices in England.ParticipantsAll patients were aged ≥18 years, with body mass index ≥30 kg/m2. A total of 537 patients were recruited; 270 received the usual care offered by their practices and 267 received the 10TT intervention.Outcomes measuresHealth service use and quality-adjusted life years (QALYs) were measured over 2 years. Analysis was conducted in terms of incremental net monetary benefits (NMBs), using non-parametric bootstrapping and multiple imputation.ResultsOver a 2-year time horizon, the mean costs and QALYs per patient in the 10TT group were £1889 (95% CI £1522 to £2566) and 1.51 (95% CI 1.44 to 1.58). The mean costs and QALYs for usual care were £1925 (95% CI £1599 to £2251) and 1.51 (95% CI 1.45 to 1.57), respectively. This generated a mean cost difference of −£36 (95% CI −£512 to £441) and a mean QALY difference of 0.001 (95% CI −0.080 to 0.082). The incremental NMB for 10TT versus usual care was £49 (95% CI −£1709 to £1800) at a maximum willingness to pay for a QALY of £20 000. 10TT had a 52% probability of being cost-effective at this threshold.ConclusionsCosts and QALYs for 10TT were not significantly different from usual care and therefore 10TT is as cost-effective as usual care. There was no evidence to recommend nor advice against offering 10TT to obese patients in general practices based on cost-effectiveness considerations.Trial registration numberISRCTN16347068; Post-results.