Objectives: To assess completeness and determinants of reporting to the AIDS registry of the Swiss Federal Office of Public Health.
Design and methods: Death certificates indicative of AIDS or HIV for deaths occurring between December 1987 and June 1990 were reviewed and compared with reports to the AIDS registry.
Results: The completeness of the AIDS registry was 68%. However, almost all cases have now been ascertained, because more than 90% of unreported AIDS cases are detected when death certificates are reviewed. Thus, the ongoing review of death certificates adds to the total case ascertainment. The most important determinant of reporting was the reporting source: specialized AIDS clinics reported 85% of their cases, while all other sources reported only 48%.
Conclusion: The investigation of the heterogeneity of reporting is important. It can wrongly suggest regional and national differences in the epidemic and lead to a decrease in completeness of reporting over time without actual changes in reporting behavior.