Major malformations of the central nervous system in Hungary.

TLDR: While planning the survey, several ways of forming an adequate control group were explored and eventually it was decided to use data of the general population of births reported in demographic books, mainly from the register of congenital malformations, for which fairly complete data were obtained.

Abstract: Data on all major central nervous system mal formations which occurred in children born in Budapest in the years 1963-67 were collected. They were divided into four categories?anencephaly, spina bifida cystica, encephalo-meningocele, and congenital hydrocephalus. During the period of the survey, 99*7 % of Budapest deliveries took place in hospital; in Hungary the proportion was 97-8%. Data were compiled from the following sources: (1) all of the 31 maternity hospitals of Budapest, where the personal data and obstetric histories of malformed infants were abstracted from the obstetric registers; (2) all of the 26 departments of pathological ana tomy in Budapest, where data relating to infants who had died of CNS malformations were taken from the necropsy records; (3) the register of Heim Pal Paediatric Hospital, which lists congenital malformations reported from the whole of Hungary including Budapest. This register was set up by directive of the Ministry of Health (40.827/1962); (4) all of the eight surgical paediatric departments in Budapest, where data of infants treated surgically for CNS malformations were obtained. The distribution of cases from the different sources is shown in Figure 1. The collected data of 'index patients' were listed on 'personal cards' in order to avoid duplication of records. While planning the survey, several ways of forming an adequate control group were explored and eventually it was decided to use data of the general population of births reported in demographic y arbooks. In a dition to the Budapest births, for which fairly complete data were obtained, details of 963 country cases were also collected, mainly from the register of congenital malformations, but these were not included in the incidence studies and served only as additional material for examining the epidemio logical characteristics of malformations and the type of inheritance. A questionnaire with reply envelope and stamp attached was sent to the mothers of affected infants