Statistical issues in pragmatic trials of behavioral economic interventions

Randomized clinical trials provide gold-standard evidence for the efficacy of interventions, but have limitations, including highly selected populations that make inference on effectiveness difficult and a lack of ability to adapt and change midstream.

We propose two innovations for pragmatic trial design.

Evidence-based evolutionary testing, a framework that allows adaptation of interventions and rapid-cycle innovation, preserves the power of randomization while acknowledging the need for adaptation and learning. An opt-out consent framework increases the fraction of the target population who participate in trials, but may lead to dampening of effect sizes.

Pragmatic trials offer numerous advantages in the evaluation of behavioral interventions in health. Statistical innovations, including evidence-based evolutionary testing and opt-out framing of consent and enrollment processes, can enhance the power of pragmatic trials and lead to more rapid progress.