Clinical trials.

Clinical trials can be used to generate data on safety, efficacy, and/or effectiveness of treatments. They can be classified based on their purpose, phase, or design. Key components of clinical trial design include: identifying the study question and population; clearly defining the treatment and comparison groups; choosing the method of treatment group allocation; defining the primary and secondary outcomes; performing a power analysis; outlining an analytic plan; and reporting results. Critical issues to consider when either designing a trial or interpreting the results of a trial include evaluating the validity and generalizability of the results and assessing the appropriateness of the control group. Designing and implementing clinical trials in pediatric surgery is challenging, but well-constructed and executed trials are instrumental in improving clinical care.