Efeito da remoção de notifi cações repetidas sobre a incidência da tuberculose no Brasil Impact on tuberculosis incidence rates of removal of repeat notifi cation records

ABSTRACT OBJECTIVE: To evaluate the impact on tuberculosis (TB) incidence rates of removal of improper duplicate records from the notifi cation system. METHODS: Data from the Sistema de Informacao de Agravos de Noti fi cacao (Brazilian Information System for Tuberculosis Noti fi cation) from 2000 to 2004 were analyzed. Repeat records were identifi ed through probabilistic record linkage and classifi ed into six mutually exclusive categories and then kept, combined or removed from database. RESULTS: Of all TB records, 73.7% had no duplicate, 18.9% were duplicate, 4.7% were triplicate, and 2.7% were quadruplicate or more. Of all repeat records, 47.3% were classifi ed as transfer in/out; 23.6% return after default, 16.4% true duplicates, 10% relapse, 2.5% inconclusive and 0.2% had missing data. These proportions were different in Brazilian states. Removal of improper duplicate records reduced TB incidence rate per 100.000 inhabitants by 6.1% in the year 2000 (from 44 to 41.3), 8.3% in 2001 (from 44.5 to 40.8), 9.4% in 2002 (from 45.8 to 41.5), 9.2% in 2003 (from 46.9 to 42.6) and 8.4% in 2004 (from 45.4 to 41.6).