Effectiveness and cost-effectiveness of text messages with or without endowment incentives for weight management in men with obesity (Game of Stones): study protocol for a randomised controlled trial

Macaulay, L. et al. (2022) Effectiveness and cost-effectiveness of text messages with or without endowment incentives for weight management in men with obesity (Game of Stones): study protocol for a randomised controlled trial. Trials, 23, 582. (doi: 10.1186/s13063-022-06504-5) (PMID:35869503) (PMCID:PMC9306253)

Abstract

Background: Obesity increases the risk of type 2 diabetes, heart disease, stroke, mobility problems and some cancers, and its prevalence is rising. Men engage less than women in existing weight loss interventions. Game of Stones builds on a successful feasibility study and aims to find out if automated text messages with or without endowment incentives are effective and cost-effective for weight loss at 12 months compared to a waiting list comparator arm in men with obesity. Methods: A 3-arm, parallel group, assessor-blind superiority randomised controlled trial with process evaluation will recruit 585 adult men with body mass index of 30 kg/m2 or more living in and around three UK centres (Belfast, Bristol, Glasgow), purposively targeting disadvantaged areas. Intervention groups: (i) automated, theory-informed text messages daily for 12 months plus endowment incentives linked to verified weight loss targets at 3, 6 and 12 months; (ii) the same text messages and weight loss assessment protocol; (iii) comparator group: 12 month waiting list, then text messages for 3 months. The primary outcome is percentage weight change at 12 months from baseline. Secondary outcomes at 12 months are as follows: quality of life, wellbeing, mental health, weight stigma, behaviours, satisfaction and confidence. Follow-up includes weight at 24 months. A health economic evaluation will measure cost-effectiveness over the trial and over modelled lifetime: including health service resource-use and quality-adjusted life years. The cost-utility analysis will report incremental cost per quality-adjusted life years gained. Participant and service provider perspectives will be explored via telephone interviews, and exploratory mixed methods process evaluation analyses will focus on mental health, multiple long-term conditions, health inequalities and implementation strategies. Discussion: The trial will report whether text messages (with and without cash incentives) can help men to lose weight over 1 year and maintain this for another year compared to a comparator group; the costs and benefits to the health service; and men’s experiences of the interventions. Process analyses with public involvement and service commissioner input will ensure that this open-source digital self-care intervention could be sustainable and scalable by a range of NHS or public services. Trial registration: ISRCTN 91974895. Registered on 14/04/2021.

• Item Type: Articles
• Additional Information: This trial is funded by the National Institute for Health and Care Research (NIHR), UK (Ref: NIHR 129,703).
• Keywords: Randomised controlled trial, Men with obesity, text messages, financial incentives, weight management, health inequalities, process evaluation, cost-effectiveness.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Gray, Professor Cindy and Hunt, Professor Kathryn and Macaulay, Dr Lisa and Dombrowski, Dr Stephan
• Authors: Macaulay, L., O’Dolan, C., Avenell, A., Carroll, P., Cotton, S., Dombrowski, S., Elders, A., Goulao, B., Gray, C., Harris, F. M., Hunt, K., Kee, F., MacLennan, G., McDonald, M. D., McKinley, M., Skinner, R., Torrens, C., Tod, M., Turner, K., van der Pol, M., and Hoddinott, P.
• College/School: College of Medical Veterinary and Life Sciences > School of Health & Wellbeing > MRC/CSO SPHSU; College of Medical Veterinary and Life Sciences > School of Health & Wellbeing > Social Scientists working in Health and Wellbeing
• Journal Name: Trials
• Publisher: BioMed Central
• ISSN: 1745-6215
• ISSN (Online): 1745-6215
• Copyright Holders: Copyright © 2022 The Authors
• First Published: First published in Trials 23: 582
• Publisher Policy: Reproduced under a Creative Commons License