National data linkage assessment of live births and deaths in Mexico: Estimating under‐five mortality rate ratios for vulnerable newborns and trends from 2008 to 2019

Abstract

Background: Linked datasets that enable longitudinal assessments are scarce in low and middle-income countries. Objectives:We aimed to assess the linkage of administrative databases of live births and under-five child deaths to explore mortality and trends for preterm, small (SGA) and large for gestational age (LGA) in Mexico. Methods:We linked individual-level datasets collected by National statistics from 2008 to 2019. Linkage was performed based on agreement on birthday, sex, residential address. We used the Centre for Data and Knowledge Integration for Health software to identify the best candidate pairs based on similarity. Accuracy was assessed by calculating the area under the receiver operating characteristic curve. We evaluated completeness by comparing the number of linked records with reported deaths. We described the percentage of linked records by baseline characteristics to identify potential bias. Using the linked dataset, we calculated mortality rate ratios (RR) in neonatal, infants, and children under-five according to gestational age, birthweight, and size.

The matrix revolutions: How databases and database linkages will transform epidemiologic research

“…The general problem of misclassification of determinant and/ or outcome status is not unique to research using databases and is well understood. Studies using the information on congenital anomalies at birth and the study by Suárez-Idueta et al 2…”

“…1 Although Relman's prediction has not come to pass, digital information systems that capture vast amounts of medical and related data are now on the verge of revolutionising the work of perinatal and other epidemiologists. This issue of Paediatric and Perinatal Epidemiology includes two articles that highlight recent developments in health information systems: Suárez-Idueta et al 2 present the results of linking live birth and death registration data (for infants and children <5 years of age) in Mexico, while Johansson et al 3 The linkage of 24 million live births to deaths in infancy and early childhood represents a significant epidemiologic success for Mexico, despite challenges related to the underestimation of deaths, and unlinked deaths. 2 A similar attempt in Canada in the 1990s resulted in a 25% rate of unlinked infant deaths in Ontario, the largest province in Canada.…”

“…This issue of Paediatric and Perinatal Epidemiology includes two articles that highlight recent developments in health information systems: Suárez-Idueta et al 2 present the results of linking live birth and death registration data (for infants and children <5 years of age) in Mexico, while Johansson et al 3 The linkage of 24 million live births to deaths in infancy and early childhood represents a significant epidemiologic success for Mexico, despite challenges related to the underestimation of deaths, and unlinked deaths. 2 A similar attempt in Canada in the 1990s resulted in a 25% rate of unlinked infant deaths in Ontario, the largest province in Canada. 4 Several investigations aimed at identifying the cause for the missing birth registrations in the vital statistics data proved unsuccessful, and ultimately led to a completely revamped perinatal program in Ontario, and live birth-infant death linkages using an alternative hospitalisation database.…”

The data giveth, but what do we take away?

“…Suárez‐Idueta and colleagues 2 describe the linkage of national live birth and death data from Mexico and provide estimates for neonatal, infant, and under‐5 childhood mortality according to birth characteristics. Johansson and colleagues 3 describe a unique population‐based longitudinal data source of mothers and their infants from the Stockholm and Gotland regions of Sweden that utilises information from medical records with linkage to national registers.…”