Reliability of treatment outcome for tuberculosis using record linkage

The quality of information is crucial in the monitoring and evaluation of control actions of diseases such as tuberculosis (TB). However, studies have pointed out deficiencies in the quality of data obtained by the TB surveillance system. Thus the aim of this study was to analyze the agreement between treatment outcome of the Notifiable Diseases Information System (SINAN) and information on the underlying and associated cause of death in the Mortality Information System (SIM). We conducted a probabilistic record linkage with the databases of the SINAN 2006 and the SIM 2006-2008. The accuracy of treatment outcome was analyzed by kappa index. Of the 417 cases closed as death in the SINAN, 88.7% were found in the SIM. Of the 82 cases closed as death from other causes, 42.7% presented TB as the underlying or associated cause in the SIM, while 41.5% did not mention TB. PABAK coefficients revealed excellent agreement between the treatment outcome of death of the SINAN and the presence or absence of TB death in the SIM. We recommend that the states and municipalities that use the linkage between the SINAN and SIM to increase the completeness and consistency of the SINAN-TB search on the SIM, not only for cases without treatment outcome, but also for those discontinued and transferred.