A 2x2 randomised factorial SWAT of the use of a pen and small, financial incentive to improve recruitment rates in a randomised controlled trial of yoga for older adults with multimorbidity

TY - JOUR

T1 - A 2x2 randomised factorial SWAT of the use of a pen and small, financial incentive to improve recruitment rates in a randomised controlled trial of yoga for older adults with multimorbidity

AU - Fairhurst, Caroline

AU - Roche, Jenny

AU - Bissell, Laura

AU - Hewitt, Catherine

AU - Hugill-Jones, Jess

AU - Howsam, Jenny

AU - Maturana, Camila S

AU - Corbacho Martin, Belen

AU - Paul, Shirley-Anne S

AU - Rose, Fi

AU - Torgerson, David J

AU - Ward, Lesley

AU - Wiley, Laura

AU - Tew, Garry A

N1 - Copyright: © 2022 Fairhurst C et al.

PY - 2021/4/27

Y1 - 2021/4/27

N2 - Background: Monetary and other incentives may increase recruitment to randomised controlled trials. Methods: 2x2 factorial ‘study within a trial’ of including a pen and/or £5 with a postal recruitment pack to improve randomisation rate (primary outcome) into the host Gentle Years Yoga trial in older adults with multimorbidity. Secondary outcomes: return, and time to return, of screening form, and the cost per additional participant recruited. Binary data were analysed using logistic regression and time to return data using Cox proportional hazards regression. Results: 818 potential host trial participants included. Between those sent a pen (n=409) and not sent a pen (n=409), there was no evidence of a difference in the likelihood of being randomised (15 (3.7%) versus 11 (2.7%); OR 1.38, 95% CI 0.63–3.04), in returning a screening form (66 (16.1%) versus 61 (14.9%); OR 1.10, 95% CI 0.75–1.61) nor in time to return the screening form (HR 1.09, 95% CI 0.77–1.55). There was evidence of improved screening return rates (77 (18.8%) versus 50 (12.2%); OR 1.67, 95% CI 1.13–2.45) and time to return screening form (HR 1.56, 95% CI 1.09–2.22) but not randomisation (14 (3.4%) versus 12 (2.9%); OR 1.18, 95% CI 0.54–2.57) in those sent £5 (n=409) compared with those not sent £5 (n=409). No significant interaction effects between the interventions were observed. The cost per additional participant recruited was £32 for the pen and £1000 for the £5 incentive.Conclusion: Including a small, monetary incentive encouraged increased and faster response to the recruitment invitation but did not result in more participants being randomised into the host trial. Since it is relatively costly, we do not recommend this intervention for use to increase recruitment in this population. Pens are cheaper but did not provide evidence of benefit. Further studies may be required. Registration: Gentle Years Yoga Trial registered on 18 March 2019, ISRCTN13567538; SWAT registered with the Northern Ireland Network for Trials Methodology Research SWAT repository on 1 April 2018, SWAT94.Funding: The GYY trial and SWATs were funded by the United Kingdom National Health Service (NHS) through the National Institute for Health Research (NIHR) Health Technology Assessment (HTA) programme, open call project number 17/94/36.Keywords: study within a trial, pen, financial incentive, recruitment, factorial, randomised controlled trial, older people, multimorbidity

AB - Background: Monetary and other incentives may increase recruitment to randomised controlled trials. Methods: 2x2 factorial ‘study within a trial’ of including a pen and/or £5 with a postal recruitment pack to improve randomisation rate (primary outcome) into the host Gentle Years Yoga trial in older adults with multimorbidity. Secondary outcomes: return, and time to return, of screening form, and the cost per additional participant recruited. Binary data were analysed using logistic regression and time to return data using Cox proportional hazards regression. Results: 818 potential host trial participants included. Between those sent a pen (n=409) and not sent a pen (n=409), there was no evidence of a difference in the likelihood of being randomised (15 (3.7%) versus 11 (2.7%); OR 1.38, 95% CI 0.63–3.04), in returning a screening form (66 (16.1%) versus 61 (14.9%); OR 1.10, 95% CI 0.75–1.61) nor in time to return the screening form (HR 1.09, 95% CI 0.77–1.55). There was evidence of improved screening return rates (77 (18.8%) versus 50 (12.2%); OR 1.67, 95% CI 1.13–2.45) and time to return screening form (HR 1.56, 95% CI 1.09–2.22) but not randomisation (14 (3.4%) versus 12 (2.9%); OR 1.18, 95% CI 0.54–2.57) in those sent £5 (n=409) compared with those not sent £5 (n=409). No significant interaction effects between the interventions were observed. The cost per additional participant recruited was £32 for the pen and £1000 for the £5 incentive.Conclusion: Including a small, monetary incentive encouraged increased and faster response to the recruitment invitation but did not result in more participants being randomised into the host trial. Since it is relatively costly, we do not recommend this intervention for use to increase recruitment in this population. Pens are cheaper but did not provide evidence of benefit. Further studies may be required. Registration: Gentle Years Yoga Trial registered on 18 March 2019, ISRCTN13567538; SWAT registered with the Northern Ireland Network for Trials Methodology Research SWAT repository on 1 April 2018, SWAT94.Funding: The GYY trial and SWATs were funded by the United Kingdom National Health Service (NHS) through the National Institute for Health Research (NIHR) Health Technology Assessment (HTA) programme, open call project number 17/94/36.Keywords: study within a trial, pen, financial incentive, recruitment, factorial, randomised controlled trial, older people, multimorbidity

KW - Aged

KW - Humans

KW - Logistic Models

KW - Motivation

KW - Multimorbidity

KW - Surveys and Questionnaires

KW - Yoga

U2 - 10.12688/f1000research.52164.2

DO - 10.12688/f1000research.52164.2

M3 - Article

C2 - 35444795

SN - 2046-1402

VL - 10

SP - 326

JO - F1000research

JF - F1000research

M1 - 326

ER -