N-of-1 trials: innovative methods to evaluate complementary and alternative medicines in pediatric cancer.

N-of-1 randomized controlled trials (RCTs) are randomized trials conducted within individuals and may be an attractive methodology for conducting studies of complementary and alternative medicine (CAM) in pediatric oncology. These trials may be used to determine the efficacy of an intervention in an individual, or multiple N-of-1 RCTs may be combined to estimate a population effect. There are many potential advantages to the use of N-of-1 RCTs with CAM in pediatric cancer. These advantages include the ability to determine whether CAM is effective in a specific child. In addition, the N-of-1 RCT allows parents and children to voice preferences about treatment options and allows them to directly participate in balancing adverse events and therapeutic benefits. Also, in estimation of population effects, combining multiple N-of-1 RCTs tends to require smaller sample sizes than do traditional parallel-group designs. However, there also may be several challenges to the conduct of such a trial. The use of N-of-1 RCTs may be very beneficial in evaluating CAM therapies in pediatric cancer. However, careful consideration of the advantages and disadvantages of such a design should be undertaken prior to initiating an N-of-1 RCT.