Caesarean section overuse and underuse across districts during health insurance expansion, India, 2015–2024: supplementary material, data and code

<p dir="ltr">This repository contains the supplementary material, analysis datasets and code for the article "Caesarean section overuse and underuse across districts during health insurance expansion, India, 2015–2024", submitted to the Bulletin of the World Health Organization.</p><p dir="ltr">The study combined district-level estimates from three rounds of India's National Family Health Survey (NFHS-4, 2015–2016; NFHS-5, 2019–2021; NFHS-6, 2023–2024) with individual-level birth data from NFHS-4 and NFHS-5 (The DHS Program).

It assessed caesarean section rates against the WHO reference range, changes in household health insurance coverage, and wealth-related and sectoral inequality. Methods included district and survey-round fixed-effects regression, spatial autocorrelation (Moran's I, LISA, Getis-Ord Gi*), spatial lag and spatial error models, geographically weighted regression, Kitagawa decomposition, Erreygers-corrected concentration indices with decomposition, survey-weighted logistic regression and inverse probability of treatment weighting.</p><p dir="ltr">Contents:<br>(1) Supplementary material: Tables S1–S9 and Fig. S1 (indicator definitions, validation against official NFHS estimates, fixed-effects models, spatial regression diagnostics and models, geographically weighted regression, Kitagawa decomposition, concentration-index decomposition, logistic regression and inverse-probability-weighted estimates).<br>(2) Analysis datasets (CSV): the district panel for the three NFHS rounds, district caesarean rate categories, spatial results for 2023–2024, the district crosswalks linking DHS to fact-sheet districts, and the shapefile polygon linkage.<br>(3) Model outputs (JSON) with every estimate reported in the article.<br>(4) Code (Python, C and JavaScript) that reproduces the district linkage, all analyses, the figures and the documents, with a README listing the run order.</p><p dir="ltr">DHS unit-level recode files are not redistributed, because The DHS Program's terms of use do not allow it.