Private Sector Provision as an "Escape Valve": The Mexico Diabetes Experiment.

This article evaluates the impact of a private supplement to Mexico's free public health system for diabetes care, focusing on Clinicas del Azucar (CdA), a private chain offering comprehensive diabetes management. Using a novel "deniers randomization" experimental design, the study finds that enrollment in CdA significantly improves diabetes control, reducing glycated hemoglobin (HbA1c) levels by about one percentage point and increasing the share of patients with controlled blood sugar by 69%. These health improvements arise primarily from increased frequency of medical visits, better medication adherence, and modest lifestyle changes, rather than superior quality of care per visit. The intervention also reduces short-term diabetes complications and generates substantial fiscal externalities by lowering public hospital costs, making the private supplement highly cost-effective. The findings suggest that private providers can alleviate capacity constraints in overstretched public systems by improving access and patient engagement, offering lessons for public sector improvements in chronic disease management.