6.1 Coding of Congenital Anomalies

One of the essential aspects of a congenital anomalies surveillance programme is its ability to efficiently generate information. Central to this process is the proper and accurate coding of the recorded diagnostic information. Coding of diagnostic information using a disease classification system allows a surveillance programme to capture and classify cases with congenital anomalies in a standardized way. Entering coded information into an electronic system makes it easier to retrieve and analyse the data. It is important to understand and follow a standardized coding system, in order to accurately and consistently classify and code the various types of congenital anomalies.

The more precise the clinical description of congenital anomalies present in a fetus or neonate, the more accurate the classification and coding that can be achieved. For example, not knowing the lesion level of spina bifida (such as cervical, thoracic or lumbar) or whether hydrocephalus is present, or either of these conditions, would result in coding the congenital anomaly as “spina bifida, unspecified”. It is important to obtain the best possible clinical description, carefully review and classify the congenital anomaly, and assign the right code(s) based on the description. To the extent possible, the database can preserve both the codes and the detailed clinical description.

Photographs of the external congenital anomalies present can supplement the clinical description and help to ensure that the proper code is assigned. Although it is relatively easy to take photographs, it requires some training to obtain the best photographs (e.g. timing, views). Please refer to Appendix J for suggestions on taking photographs of fetuses or neonates with congenital anomalies. Privacy issues also need to be considered and appropriate measures to ensure confidentiality should be in place. Because some photographs may identify the neonate, it is critical to maintain these securely as confidential surveillance documents. More information on privacy and confidentiality is included in Chapter 2.