Barriers and enablers to recruiting participants within paediatric perioperative and anaesthetic settings: lessons learned from a trial of melatonin versus midazolam in the premedication of anxious children (the MAGIC trial)

Background: Poor recruitment is one key reason for premature closure of randomised controlled trials. The Melatonin for Anxiety prior to General Anaesthesia In Children (MAGIC) trial was a multicentre randomised controlled trial of melatonin vs midazolam in the premedication of anxious children, before surgery. The trial ran between 2019 and 2022, closing early because of recruitment futility. This paper describes the challenges that arose during the trial and offers recommendations for the design of future perioperative trials.

Methods: A case-based approach was used to identify barriers to recruitment. As part of a qualitative sub-study, semi-structured interviews with local site teams, participants, and caregivers also explored barriers and enablers to recruitment.

Results: Issues encountered included time sensitivity within pressured environments; feasibility of paediatric assent; research pharmacy availability; variation in anaesthetist equipoise; multifactorial decision-making issues in premedication selection; and the Associate Principal Investigator scheme being unable to support trials within anaesthetic trainee rotations. Future paediatric perioperative medicine trials could consider funding for research pharmacy outside of working hours; conducting risk assessments for study drugs to be held on theatre admission units; and a tailored design of site feasibility assessments to help address variation in practice. Challenges remain for the feasibility of including anaesthetic trainees within the Associate Principal Investigator scheme structure.

Conclusions: There are significant challenges to recruitment for paediatric clinical trials in anaesthesia and perioperative medicine. The MAGIC trial highlighted variations within anaesthetic practice at individual, local, and regional levels. Lessons learned from the MAGIC trial identifies specific barriers to paediatric trial enrolment, offer solutions and discusses ongoing challenges. Clinical trial registration: ISRCTN registry: ISRCTN18296119.