Indirect technique to estimate neonatal, infant, and under-five mortality rates for India and its states: A population-based cross-sectional study

Background Accurate assessment of child mortality rates is essential for policy formulation, resource allocation, and tracking progress toward Sustainable Development Goal-3 (SDG-3). The study of child mortality provides useful information to know the demographic situation of country. The death is vital event and recorded through the civil registration system. But in many developing countries, the quality of registered death is not very much reliable due to illiteracy and ignorance in population. So, the lack of accurate registration of death has forced demographers to explore the indirect techniques for estimating child mortality. In this paper, authors have utilized an indirect technique for estimating neonatal, infant and under-five mortality rate by using data on proportion of dead children and proportion of 4 + birth-order. Methods The method is mainly based on technique of linear line regression analysis, where the proportion of dead infants among all children born to currently married females (15–49 years) and proportion of 4 + birth order are taken as the independent variables and the neonatal mortality rate, or infant mortality rate, or under-five mortality rate are used as the dependent variable. This study is based on data collected in fifth round of National Family Health Survey (NFHS), 2019−21. After applying the inclusion criteria, a total of 512,408 currently married women aged 15–49 years were included in the analysis. Result For above mentioned child mortalities are calculated for India as well its major states. The actual and predicted mortality rates overlapped substantially when both predictors were used together, indicating the suitability of the proposed model. The combined-predictor models (proportion of dead children and proportion of 4 + birth-order) achieved higher R² values (0.91 for neonatal mortality rate (NMR), 0.92 for infant mortality rate (IMR), and 0.96 for under-five mortality rate (U5MR) along with the minor percentage differences between observed and estimated rates (mostly within ±10%) than single-predictor models. Conclusion The findings suggest that integrating both the predictors, proportion of dead children and the proportion of higher birth order children improves the accuracy of indirect estimates of NMR, IMR, and U5MR. This approach may serve as a practical tool for generating timely mortality estimates in contexts where civil registration and survey data are incomplete or infrequent.