Improving the Rigor of Mechanistic Behavioral Science: The Introduction of the Checklist for Investigating Mechanisms in Behavior-Change Research (CLIMBR)

•CLIMBR is a checklist promoting mechanism-focused behavioral intervention science.•It focuses on modifiable mechanisms that underlie successful behavior change.•It ensures that research is conducted rigorously and reported transparently.•The present manuscript describes CLIMBR’s rationale and development.