Advancing cluster randomised trials in children’s therapy: a survey of the acceptability of trial behaviours to therapists and parents

BACKGROUND: Randomised controlled trials of non-pharmacological interventions in children’s therapy are rare. This is, in part, due to the challenges of the acceptability of common trial designs to therapists and service users. This study investigated the acceptability of participation in cluster randomised controlled trials to therapists and service users. METHODS: A national electronic survey of UK occupational therapists, physiotherapists, speech and language therapists, service managers, and parents of children who use their services. Participants were recruited by NHS Trusts sharing a link to an online questionnaire with children’s therapists in their Trust and with parents via Trust social media channels. National professional and parent networks also recruited to the survey. We aimed for a sample size of 325 therapists, 30 service managers, and 60 parents. Trial participation was operationalised as three behaviours undertaken by both therapists and parents: agreeing to take part in a trial, discussing a trial, and sharing information with a research team. Acceptability of the behaviours was measured using an online questionnaire based on the Theoretical Framework of Acceptability constructs: affective attitude, self-efficacy, and burden. The general acceptability of trials was measured using the acceptability constructs of intervention coherence and perceived effectiveness. Data were collected from June to September 2020. Numerical data were analysed using descriptive statistics and textual data by descriptive summary. RESULTS: A total of 345 survey responses were recorded. Following exclusions, 249 therapists and 40 parents provided data which was 69.6% (289/415) of the target sample size. It was not possible to track the number of people invited to take the survey nor those who viewed, but did not complete, the online questionnaire for calculation of response rates. A completion rate (participants who completed the last page of the survey divided by the participants who completed the first, mandatory, page of the survey) of 42.9% was achieved. Of the three specified trial behaviours, 140/249 (56.2%) therapists were least confident about agreeing to take part in a trial. Therapists (135/249, 52.6%) reported some confidence they could discuss a trial with a parent and child at an appointment. One hundred twenty of 249 (48.2%) therapists reported confidence in sharing information with a research team through questionnaires and interviews or sharing routine health data. Therapists (140/249, 56.2%) felt that taking part in the trial would take a lot of effort and resources. Support and resources, confidence with intervention allocation, and sense of control and professional autonomy over clinical practice were factors that positively affected the acceptability of trials. Of the 40 parents, twelve provided complete data. Most parents (18/40, 45%) agreed that it was clear how trials improve children’s therapies and outcomes and that a cluster randomised trial made sense to them in their therapy situation (12/29, 30%). CONCLUSIONS: Using trials to evaluate therapy interventions is, in principle, acceptable to therapists, but their willingness to participate in trials is variable. The willingness to participate may be particularly influenced by their views related to the burden associated with trials, intervention allocation, and professional autonomy.