[The national patient register--a research tool?].

In connection with an analysis of rupture of the uterus in Denmark during the period 1980-1987, the authors found that 956 patients were registered as having rupture of the uterus in the Danish national patient register. Review of the individual cases revealed that the correct number was only 129, i.e. that only 14.1% were correctly registered. The authors consider it unsatisfactory that such an extensive register of this type cannot be employed without controlling the records of each individual patient.