Declining Induced Abortion Rate in Finland: Data Quality of the Finnish Abortion Register

Background Induced abortion rates have declined in Finland since 1973. A possible explanation offered has been that of deteriorating data collection. Methods To assess the completeness of the Register, we compared the information from a consecutive sample of hospital records (N = 482) to the Finnish Abortion Register in 18 hospitals in three counties. A smaller consecutive sample (N = 345) was collected from the same hospitals to assess the validity of the Register information. Results Only five abortions (1%) found in the hospitals were not reported in the Abortion Register. A total of 95% of all Register information was identical to that in the medical records. There were quality problems in reporting some variables: the length of pregnancy (definition problems), the classification of the abortion procedure, and social class (out-of-date classifications). Furthermore, early complications were poorty reported. Conclusions The data from the Finnish Abortion Register are a reliable sources for monitoring trends in the abortion rate and its variation by subgroups, but are an unreliable source for the study of the medical aspects of induced abortion.