Background India’s upcoming parliamentary delimitation, based solely on population size, risks penalising states with successful public health and birth control policies amid concerns about reduced representation in the South. No previous study has integrated health metrics into electoral representation. The study developed and tested a health-weighted delimitation model that includes public health metrics to ensure equitable electoral representation while preserving the current allocation of seats.

Methods Data for all 28 states and 8 UTs were compiled from the National Family Health Survey-5, Sample Registration System, and Census 2011. Five indicators, like projected population (2021), infant mortality rate (IMR), maternal mortality ratio (MMR), total fertility rate (TFR), and female literacy, were normalised. TFR, IMR, and MMR were reverse-scored so that higher values reflected better health performance. Principal component analysis (PCA), conducted using R software, generated a composite Health-Weighted Performance Score (HWPS), with the first principal component explaining 70.3% of the total variance. Seats were allocated in proportion to HWPS under three scenarios: the current allocation (543 seats), a 10% expansion (597 seats), and a 15% expansion (625 seats). The algorithm guaranteed that no region received fewer seats than in 2019 and capped increases at 10% or 15%. Robustness was assessed using 1,000 Monte Carlo simulations (+/-10% Gaussian noise) and +/-20% sensitivity analyses.

Results The HWPS ranged from 1 (Bihar) to 100 (Lakshadweep), with higher scores in states with strong health and literacy outcomes. Under a 10% expansion, 26 of 36 regions gained seats, with none losing representation. Health-advanced Kerala increased from 20 (in 2019) to 22 seats (in a 597-seat scenario). Populous states like Bihar and Uttar Pradesh received modest increases. The Seat allocations remained consistent across simulations and sensitivity analyses (+/-1 seat in 95% simulations).

Conclusions The health-weighted parliamentary seat allocation model is a novel and transparent framework that integrates public health into political representation. This model promotes electoral equity by maintaining current representation and rewarding health progress.

The authors have declared no competing interest.

This study did not receive any funding

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