Does home-based screening and health information provision improve hypertension diagnosis, treatment, and control? A regression discontinuity analysis in urban India

Background: In India, several state governments are implementing or considering home-based hypertension screening programs to improve population-wide diagnosis and blood pressure (BP) control rates. However, there is limited evidence on the effectiveness of home-based screening programs in India. Methods: Using six waves of population-representative cohort data (N = 15,573), we estimate the causal effect of a home-based hypertension screening intervention on diagnosis, treatment, and BP using a novel application of the Regression Discontinuity Design. Findings: We find that screening individuals' BP in their homes and providing health information and a referral to those with elevated BP did not meaningfully improve hypertension diagnosis (0.1, p-value: 0.82), treatment (-0.2, p-value: 0.49), or BP levels (systolic: -1.8, p-value: 0.03; diastolic: 0.5, p-value: 0.39). This null effect is robust across subpopulations and alternative specifications. Interpretation: Our findings suggest that a lack of knowledge of one's hypertension status might not be the primary reason for low diagnosis and treatment rates in India, where other structural and behavioral barriers may be more relevant. Adapting screening efforts to address these additional barriers will be essential for translating India's screening efforts into improved population health.