Medical Sociology of Community Health Worker Diagnostic Algorithm Updates and Referral Accuracy for Childhood Febrile Illness in Ugandan Village Health Teams: A Stepped-Wedge Implementation Evaluation

Stepped-wedge designs are increasingly used to evaluate health-system interventions in low-income settings, yet their operating characteristics for binary referral outcomes in small cluster counts remain poorly characterised. The analysis was conducted as a design and power study; no observational data were used or claimed. Power rose with cluster count and effect size, and 56 clusters were required to detect a 5-percentage-point effect at 80% power. Minimum detectable effect declined monotonically with cluster count. The results indicate that stepped-wedge evaluations of community health worker diagnostic algorithm updates in Ugandan Village Health Teams are underpowered at the cluster counts typically available, and that the before-after-control-impact estimator's operating characteristics impose a design constraint that medical sociology must confront before referral-accuracy claims can be sustained.