Stepped-wedge trials should be classified as research for the purpose of ethical review.

Through an ethical analysis of two case studies, we argue that stepped-wedge trials, like parallel arm cluster trials, are systematic investigations designed to produce generalizable knowledge. We contend that stepped-wedge trials usually include human research participants, which may be patients, health care providers, or both. Stepped-wedge trials are therefore research involving human participants for the purpose of ethical review. Nevertheless, the use of a waiver or alteration of consent may be appropriate in many stepped-wedge trials due to the infeasibility of obtaining informed consent and the low-risk nature of the interventions. To ensure that traditional ethical principles such as respect for persons are upheld, these studies must undergo research ethics review.