Background: Randomized controlled trials are powerful tools to evaluate the outcomes of clinical treatments. However, these trials tend to be expensive and time-consuming, and their conclusions can be threatened by several limitations. This study estimated the strength of three common limitations (underenrollment, selective enrollment, and nonadherence to protocol) in a proposed study of adolescent idiopathic scoliosis.

Methods: Patients with scoliosis and their parents were asked to complete a web-based survey about their preferences concerning a hypothetical randomized trial. Adolescents without scoliosis and their parents also participated. Surveys included questions about treatment preference, likelihood of participation, required risk reduction, and propensity to drop out or choose a different treatment while enrolled in the study.

Results: Ninety adolescents and eighty-three parents participated. Observation was preferred to bracing by the majority of subjects. Overall, 33% of the parents and adolescents would both agree to participate in the hypothetical trial. Of the subjects who would not agree to participate, the majority would rather share the decision-making responsibility with the physician than have the treatment chosen in a random fashion. Many of the subjects would consider changing treatments during the course of the trial if they were not satisfied with the outcomes; the majority of parents who preferred bracing would consider crossing over to the bracing arm if their children were randomized to observation.

Conclusions: Recruitment into a randomized trial of bracing compared with observation for the treatment of adolescent idiopathic scoliosis may well be problematic, considering the relatively small percentage of families who said they would consider randomization. Additionally, the threat of nonadherence to protocol may be strong and must be addressed in the protocol of the trial. Most families wanted to make the treatment decision with the physician in lieu of randomization; therefore, the role of the physician in patient recruitment and retention should not be underestimated.