Core outcome set for intervention research on snakebite envenomation in South Asia

Background The 2019 WHO strategy to reduce snakebite burden emphasises the need for fostering research on snakebite treatments. A core outcome set (COS) is a consensus minimal list of outcomes that should be measured in research on a particular condition. We aimed to develop a COS for snakebite research in South Asia, the region with the highest burden. Methods We used data from a systematic review of outcomes to develop a long list of outcomes which were rated in two rounds of online Delphi survey with healthcare providers, patients and the public, and potential COS users to develop a COS for intervention research on snakebite treatments in South Asia for five intervention groups. Subsequently, meetings, consultations and workshops were organised to reach further consensus. We defined the consensus criteria a priori. Results Overall, 72 and 61 people, including patients and the public, participated in round I and round II of the Delphi, respectively. Consensus COSs (including definition and time points) were developed for interventions that prevent adverse reaction to snake antivenom (three outcomes), specifically manage neurotoxic manifestations (five outcomes), specifically manage haematological manifestations (five outcomes) and those that act against snake venom (seven) outcomes. A priori criteria for inclusion in COS were not met for COS on interventions for management of the bitten part. Conclusion The COS contributes to improving research efficiency by standardising outcome measurement in South Asia. It also provides methodological insights for future development of COS, beyond snakebite. All data relevant to the study are included in the article or uploaded as online supplemental information. Data relevant to the study are either presented in the paper or in the appendix.