Effects of Cash Transfer and Incentive Programs on Service Utilization and Treatment Outcomes Related to Neglected Tropical Diseases and Their Impact on Health and Nutrition in Low- and Middle-Income Countries: Protocol for a Systematic Review.

Background: Despite a global decreasing trend in neglected tropical diseases (NTDs), progress is not on track to meet the Sustainable Development Goals by 2030. Evidence suggests a positive effect of conditional cash transfer programs on controlling NTDs. However, it remains to be evaluated whether other financial incentive programs exert similar effects on NTD-related service utilization and treatment outcomes in low- and middle-income countries (LMICs). Objective: This systematic review aims to evaluate the effects of cash transfer and incentive programs on NTD-related service utilization and treatment outcomes in LMICs; to examine how covariates, program design, and implementation plan influence these outcomes; and to examine how NTD-related service utilization and treatment outcomes influence nutritional status and health in LMICs. Methods: This review will follow the PICOS (Population, Interventions, Comparators, Outcomes, Study Design) framework. The population of this review will be restricted to adults and children of all ages in LMICs. For intervention selection, we will include any program or policies addressing socioeconomic disadvantage through the provision of cash transfers or incentive programs, including but not limited to in-kind transfers, food vouchers, free medicine vouchers, discount coupons, and microcredit to households or individuals. Eligible comparators will be the population who did not receive any intervention, recipients of interventions from before the intervention, and populations or areas exposed to different levels of intervention coverage. The primary outcomes will be service utilization and treatment outcomes related to any of the 21 NTDs prioritized by the World Health Organization. Studies without any financial incentive intervention will be excluded. Studies available in English between 2000 and 2024 will be searched in databases, including PubMed, Google Scholar, Scopus, Cochrane, Embase, and CINAHL. Screening, data extraction, and risk of bias assessment will be conducted independently by two reviewers, and discrepancies, if any, would be resolved by a third reviewer. Quality assessment will use the Revised Cochrane Risk of Bias for randomized trials (RoB 2), Risk of Bias in Non-Randomized Studies of Interventions (ROBINS-I), the Joanna Briggs Institute (JBI) checklist for cross-sectional studies, and the Critical Appraisal Skills Programme (CASP) tool for qualitative studies. Data synthesis will involve narrative summaries by tables and figures, a meta-analysis will be undertaken, and subgroup analyses will be performed where feasible. Results: This project is supported by the Children's Investment Fund Foundation and was funded in March 2024. As of January 15, 2026, article search and title-abstract screening have been completed, and full-text screening is expected to be completed by February 2026. Findings will then be synthesized and reported by the end of April 2026. Conclusions: The limitations of the study may include potential language bias and methodological heterogeneity, which may limit the feasibility of meta-analysis. The findings of this review will inform policymakers in developing more effective strategic plans for controlling NTDs in LMICs.