BINOCAR Registers
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British Isles Network of Congenital Anomaly Registers

Data Collection

 

Case Definition

 

A congenital anomaly is defined as any defect, probably originating before birth, and includes structural, chromosomal, genetic and biochemical defects and malformations.  Each anomaly (with no maximum limit per child) is coded using the ICD-10 classification system.  Cases notified to the Register as having a syndrome are coded as such.  In addition the specified individual anomalies are also coded.  Anomalies that have not been confirmed by clinical or diagnostic tests are recorded as such as followed up for confirmation.  Suspected anomalies are largely confined to anomalies found on ultrasound examination in pregnancies that have not yet delivered.  UItrasound diagnosed soft markers are also notified to the registers, and used in the evaluation of prenatal diagnosis and screening programmes. 

 

Some anomalies do not need to be notified.  Please click here for the list of minor anomalies for exclusion.

 

Data are collected concerning all live births, stillbirths, terminations of pregnancy or spontaneous pregnancy losses with a congenital anomaly, born to residents of the geographically defined population covered by each register.

 

Ascertainment of Data

 

The BINOCAR registers need to achieve high levels of ascertainment and completeness of information about congenital anomalies in order to be effective.  This is only achieved if they collect information from multiple sources.  These sources include cytogenetic laboratories, chemical pathology laboratories, post mortem reports, coroner's reports, parents, ultrasound departments, delivery suites, obstetric notes, neonatal units, child health systems, in-patient administration systems and paediatric notes.

 

The majority of notifications are received on each Register's own notification form (example included with the MREC application).  Other notifications are derived from birth notifications, maternity discharge forms, cytogenetic laboratories, neonatal screening and post mortem reports, other anomaly registers and, previously, from CMACE and NCAS notification forms.  An example of the data flows to and from Registers is provided in an example with the MREC application.  The majority of anomalies are notified either antenatally or soon after birth.  At present, relatively few notifications of anomalies diagnosed postnatally are received, although the majority of registers welcome these later notifications.

 

Notifications relating to the same case from multiple sources are encouraged since this maximises the details available.  Notifiers encounter an affected pregnancy at various stages, both before and after delivery, when additional and different details can be provided.  Multiple source notification thus enables records to be continually updated and validated, and offered considerable advantages over the national system that traditionally relied solely on borth notification forms, and was therefore limited to reporting only anomalies evident at birth.  This aspect of regional registers, which had already assumed increasing significance following the introduction of a new electronic birth notification form throughout the United Kingdom in October 2002 that did not include details of anomalies diagnosed at birth, has now become supremely important since the closure of the national congenital anomaly surveillance system.