The tribulations of trials: Lessons learnt recruiting 777 older adults into REtirement in ACTion (REACT), a trial of a community, group-based active ageing intervention targeting mobility disability

This is the author accepted manuscriptBackground: Challenges of recruitment to randomised controlled trials (RCTs) and successful strategies to overcome them should be clearly reported to improve recruitment into future trials. REtirement in ACTion (REACT) is a UK-based multi-centre RCT recruiting older adults at high risk of mobility disability to a 12-month group-based exercise and behaviour maintenance programme or to a minimal Healthy Ageing control intervention. Methods:The recruitment target was 768 adults, aged 65 years and older scoring 4 to 9 on the Short Physical Performance Battery (SPPB). Recruitment methods included: a) invitations mailed by General Practitioners (GPs); b) invitations distributed via third sector organisations; c) public relations (PR) campaign. Yields, efficiency and costs were calculated. Results: The study recruited 777 (33.9% men) community-dwelling, older adults (mean age 77.55 years (SD 6.79), mean SPPB score 7.37 (SD 1.56)), 95.11% white (n=739) and broadly representative of UK quintiles of deprivation. Over a 20-month recruitment period, 25,559 invitations were issued. Eighty-eight percent of participants were recruited via GP invitations, 5.4% via the PR campaign, 3% via word-of-mouth and 2.5% via third sector organisations. Mean recruitment cost per participant was £78.47, with an extra £26.54 per recruit paid to GPs to cover research costs. Conclusions: REACT successfully recruited to target. Response rates were lower than initially predicted and recruitment timescales required adjustment. Written invitations from General Practitioners were the most efficient method for recruiting older adults at risk of mobility disability. Targeted efforts could achieve more ethnically diverse cohorts. All trials should be required to provide recruitment data to enable evidence-based planning of future trials.National Institute for Health Research, Public Health Research Programm