Spatial Inequalities in the Completeness of Under Five Deaths: Assessing Vital Registration Data in Türkiye

The neonatal, infant and under-5 mortality rates are important indicators of child health used by countries to monitor their health policies and for international comparisons. Coverage and completeness of registration systems are critical for the quality of these indicators. However, under registration of deaths is still a major problem today, especially where registration systems are still in the process of being established, particularly in low- and middle-income countries. In the last two decades, Türkiye stands out with its rapidly declining child and infant mortality, as well as its developing VR system. However, the completeness of under-5 deaths in the VR system in Türkiye has not been fully evaluated yet. The fact that the regions in Türkiye that are disadvantaged in terms of early-age mortality are less populated poses the risk of neglecting areas that need more investment and improvement in child mortality and data quality. In this study, we assess the completeness of under-5 deaths at the national and regional levels by using a recently developed model for estimating under-5 mortality by detailed age. We apply this model at both the national and regional levels to assess the completeness of under-5 deaths in the VR system of Türkiye from 2009 to 2022. The results confirm the presence of early death omission in the eastern regions at the beginning of the studied period, for which we propose a correction. The prediction of the model also indicates a strong improvement over time in the completeness of death registration in these regions. This study stresses the importance of revealing regional disadvantages rather than relying on national progress in the completeness of under five deaths, especially in low- and middle-income countries where registration systems are still in the process of being established.