A review of key terminology and definitions used for birth defects globally

Abstract

Birth defects, also known as congenital disorders, are a significant health issue impacting at least five million births annually worldwide. For policymakers to mount a relevant healthcare response to care for those affected, the burden of disease of these conditions must be quantified. Estimates of the contribution of birth defects to under-5 child mortality and morbidity are generated by several groups globally. These estimates often differ, causing confusion for policymakers. While some differences may be attributed to the data sources and methods used, much is due to a lack of clarity in the terminology used for the group of disorders classed as "congenital". This study aimed to gain insight into the diversity of terms and definitions for birth defects, including those used routinely by relevant international/national organisations and in the peer-reviewed literature. This two-part study included (1) scoping review of peer-reviewed literature to identify terms and definitions in use for birth defects and (2) review of key websites and grey literature to identify terms and definitions used. The results of this study indicate a wide variety of terms being used, often interchangeably and undefined, in peer-reviewed publications, on institutional websites and related literature. This suggests a lack of clarity related to terminology and sets the scene for further discussion, recommending that the community of practice working on birth defects comes to a consensus on standard terminology and definitions for global uptake and implementation. Such standardisation will facilitate a common understanding of the burden of these disorders globally, regionally and within countries so that action can be taken to support affected children and their families.

Keywords: Birth defects; Burden of disease; Congenital anomalies; Congenital disorders; Definitions; Terminology.

Fig. 1

A breakdown of the WHO definition of congenital disorders showing how the main disorder groupings are bundled for different professional purposes and possibilities for confusion in the absence of clear definitions. Reproduced with author permission from Modell et al. . Epidemiological methods in community genetics and the Modell Global Database of Congenital Disorders (MGDb). https://discovery.ucl.ac.uk/id/eprint/1532179/

Fig. 2

Top 20 terms resulting from individual PubMed searches from 2002 to 2022

Fig. 3

Number of publications in PubMed searches for three key search terms: “Birth defect*”, “congenital disorder*” and “congenital anom*” searching on title and abstract [tiab] from 2002 to 2022