Methods

Abstract

Punching documents were developed from the Zählkarte. The available data are written on these punching documents in coded form and then transferred to punched cards by punch operators. The punched card is one of the most frequently used devices for reading data in fields where information is basically numerical (for instance, laboratory results). All nonnumerical data must be coded before the punching process, a disadvantage that can be eliminated in other systems (see below). The registration of personal patient data (name, sex, date of birth, marital status, residence) on punching documents presents no real difficulties because the items of data are well defined. Problems arise with the documentation of diagnoses. A standard classification system does not exist. For instance, WHO’s international key for diagnoses is not generally accepted in the field of neurology. Individual codes are used (Seitz, 1973), which makes standardized documentation difficult. In the field of psychiatry the international code is in general use in Germany (Helmchen, 1974), and a common system of recording patients’ personal data and diagnoses is possible (Eckmann et al., 1973).