Macaulay, LisaO’Dolan, CatrionaAvenell, AlisonCarroll, PaulaCotton, SeonaidhDombrowski, StephanElders, AndrewGoulao, BeatrizGray, CindyHarris, Fiona M.Hunt, KateKee, FrankMacLennan, GraemeMcDonald, Matthew DavidMcKinley, MichelleSkinner, RebeccaTorrens, ClaireTod, MartinTurner, Katrinavan der Pol, MarjonHoddinott, Pat2022-07-222022-07-222022-07-22Macaulay, 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 & Hoddinott, P 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, vol. 23, no. 1, 582. https://doi.org/10.1186/s13063-022-06504-51745-6215RIS: urn:F2F54517C33F942187F45DC89969D781RIS: Macaulay2022ORCID: /0000-0002-1039-5646/work/116418050ORCID: /0000-0003-4813-5628/work/167120281https://hdl.handle.net/2164/18910Acknowledgements The authors would like to thank all the trial feldworkers for their work on recruitment and data collection: Kathryn Machray (University of Stirling); Clare Jess and Christina O’Neill (Queen’s University Belfast); Hilary Taylor and Jack Brazier, University of Bristol). We thank GP practices and local stakeholders who have advertised the trial; PPI contributors; Clinical Research Networks and men for participating during challenging times. We would also like to thank the independent members of the TSC: Edmund Juszczak – Chair (University of Nottingham); Emma Frew (University of Birmingham), David Gardner (lay member and Chairman of Scottish Men’s Sheds); Graham Jameson (lay member and participant in FFIT trial), Kate Jolly (University of Birmingham); and Jim McManus, Director of Public Health for Hertfordshire County Council) for their oversight and guidance. We are grateful for the technical/admin support and database/website development by Mark Forrest, Alina Uyazina, Connor Keegan, Kirsty McCormack and the team at CHaRT (University of Aberdeen), Jack Gilmore, Keith Milburn and Claire Jones at HIC (University of Dundee) who delivered the SMS text interventions and developed the participant tracker software and also extend thanks to administrative support from Karen Stanton, Karen Murray and Joy Taylor at the University of Stirling. Funding 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.192366582engSDG 3 - Good Health and Well-beingRandomised controlled trialMen with obesityText messagesFinancial incentivesWeight managementHealth inequalitiesProcess evaluationCost-efectivenessR MedicineNational Institute for Health Research (NIHR)NIHR 129,703Supplementary InformationRJournal article10.1186/s13063-022-06504-5231