Development of core outcome sets for effectiveness trials focused on infants and children with wasting and nutritional oedema.

INTRODUCTION: The 2023 WHO guideline on the prevention and management of wasting and nutritional oedema includes recommendations informed by best evidence from systematic reviews addressing critical and important outcomes. Multiple outcomes across trials were a challenge during guideline development, highlighting a need to establish core outcome sets (COS) for wasting and nutritional oedema. Informed by Core Outcome Measures in Effectiveness Trials (COMET) Initiative best practice methods, we aimed to develop six COS for effectiveness trials around prevention and management of wasting and nutritional oedema in infants and children. METHODS: Guideline Development Group and UNICEF/WHO Technical Advisory Group on Wasting and Nutritional Oedema members were invited to participate in a Delphi process to establish these COS. This involved scoring outcomes in two rounds of a survey (Likert scale from 1 to 9), with consensus in the second round defined as a minimum of 70% of the expert panel giving a score of at least 7 and <15% scoring 3 or below. RESULTS: Twenty-five of 36 invited participants completed each survey, followed by multiple consensus meetings to reach agreement on the outcomes. Through this Delphi process, we developed six COS for infants <6 months of age with wasting and/or nutritional oedema and/or underweight in (1) inpatient and (2) outpatient/community settings, infants and children 6-59 months of age with severe wasting and/or nutritional oedema in (3) inpatient and (4) outpatient/community settings, infants and children 6-59 months of age with moderate wasting in (5) outpatient/community settings and (6) prevention of wasting and nutritional oedema. CONCLUSION: Primary research, future guidelines and related decision-making stand to be strengthened by these six COS, including the most critical outcomes from a child health perspective to be evaluated in future effectiveness trials on wasting and nutritional oedema. Uptake of these COS will inform their further development.