An examination of the effects of a patient-designed-and-informed participant information sheet in comparison with a standard, researcher-designed information sheet on recruitment, retention and understanding: Protocol for a study-within-a-trial.

Background: This protocol describes a double-blind, randomised non-inferiority study-within-a-trial (SWAT), comparing the effects of a patient-designed-and-informed participant information sheet with a standard, researcher-designed participant information sheet on recruitment, retention, decision certainty, participant information sheet understanding and likeability. The SWAT is part of a larger trial that aims to evaluate the feasibility and preliminary efficacy of a cognitive occupation-based programme for people with MS (COB-MS) on cognitive and daily functioning for people with multiple sclerosis. Methods: During the study, 120 people with multiple sclerosis will be randomly allocated to one of the two groups, where they will either receive a standard participant information sheet or a patient-designed participant information sheet. Recruitment and retention will be analysed, as well as decision certainty, likability and understanding. Discussion: Results will provide recommendations for recruitment, consent and retention for future trials, as well as shed some light on the factors influencing the understanding and likeability of a trial's participant information sheet. Recommendations will also be made regarding patient and public involvement in developing and/or aiding the development of participant information sheets.  Registration: SWAT: Northern Ireland Hub for Trials Methodology Research SWAT Repository Store ( SWAT105). COB-MS trial: ISRCTN11462710.