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

TY - JOUR

T1 - Effectiveness and cost-effectiveness of text messages with or without endowment incentives for weight management in men with obesity (Game of Stones)

T2 - study protocol for a randomised controlled trial

AU - Macaulay, Lisa

AU - O'Dolan, Catriona

AU - Avenell, Alison

AU - Carroll, Paula

AU - Cotton, Seonaidh

AU - Dombrowski, Stephan

AU - Elders, Andrew

AU - Goulao, Beatriz

AU - Gray, Cindy

AU - Harris, Fiona M.

AU - Hunt, Kate

AU - Kee, Frank

AU - MacLennan, Graeme

AU - McDonald, Matthew David

AU - McKinley, Michelle

AU - Skinner, Rebecca

AU - Torrens, Claire

AU - Tod, Martin

AU - Turner, Katrina

AU - van der Pol, Marjon

AU - Hoddinott, Pat

N1 - Funding Information: This trial is funded by the National Institute for Health and Care Research (NIHR), UK (Ref: NIHR 129,703). The views expressed are those of the author(s) and not necessarily those of the NIHR or the Department of Health and Social Care. The funder does not have a role in the design (beyond their review of the application), analysis, interpretation of data or in writing the manuscript. © 2022. The Author(s).

PY - 2022/7/22

Y1 - 2022/7/22

N2 - 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.

AB - 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.

KW - Randomised controlled trial

KW - Men with obesity

KW - Text messages

KW - Financial incentives

KW - Weight management

KW - Health inequalities

KW - Process evaluation

KW - Cost-effectiveness

U2 - 10.1186/s13063-022-06504-5

DO - 10.1186/s13063-022-06504-5

M3 - Article

C2 - 35869503

SN - 1745-6215

VL - 23

JO - Trials

JF - Trials

IS - 1

M1 - 582

ER -