Exploring fidelity of enactment in a cluster randomised controlled trial testing the effectiveness of 'gatekeeper' training for pesticide vendors in reducing self-poisoning in rural Sri Lanka: protocol for a multimethod qualitative study.

The study was approved by the Ethics and Research Committee, Faculty of Medicine and Allied Sciences, at the Rajarata University of Sri Lanka (ERC/2023/09). All participants will provide informed consent. Findings will be disseminated in scientific peer-reviewed journals and conference presentations.