An optimised patient information sheet did not significantly increase recruitment or retention in a falls prevention study: an embedded randomised recruitment trial

BACKGROUND: Randomised controlled trials are generally regarded as the ‘gold standard’ experimental design to determine the effectiveness of an intervention. Unfortunately, many trials either fail to recruit sufficient numbers of participants, or recruitment takes longer than anticipated. The current embedded trial evaluates the effectiveness of optimised patient information sheets on recruitment of participants in a falls prevention trial. METHODS: A three-arm, embedded randomised methodology trial was conducted within the National Institute for Health Research-funded REducing Falls with ORthoses and a Multifaceted podiatry intervention (REFORM) cohort randomised controlled trial. Routine National Health Service podiatry patients over the age of 65 were randomised to receive either the control patient information sheet (PIS) for the host trial or one of two optimised versions, a bespoke user-tested PIS or a template-developed PIS. The primary outcome was the proportion of patients in each group who went on to be randomised to the host trial. RESULTS: Six thousand and nine hundred patients were randomised 1:1:1 into the embedded trial. A total of 193 (2.8%) went on to be randomised into the main REFORM trial (control n = 62, template-developed n = 68; bespoke user-tested n = 63). Information sheet allocation did not improve recruitment to the trial (odds ratios for the three pairwise comparisons: template vs control 1.10 (95% CI 0.77–1.56, p = 0.60); user-tested vs control 1.01 (95% CI 0.71–1.45, p = 0.94); and user-tested vs template 0.92 (95% CI 0.65–1.31, p = 0.65)). CONCLUSIONS: This embedded methodology trial has demonstrated limited evidence as to the benefit of using optimised information materials on recruitment and retention rates in the REFORM study. TRIAL REGISTRATION: International Standard Randomised Controlled Trials Number registry, ISRCTN68240461. Registered on 01 July 2011. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13063-017-1797-7) contains supplementary material, which is available to authorized users.