Accuracy and completeness of recording of confirmed tuberculosis in two South African communities

Although tuberculosis (TB) treatment registers and laboratory records are essential tools for recording and reporting in TB control programmes, the accuracy and completeness of routinely collected data are seldom monitored.

To assess the accuracy and completeness of TB treatment register data in two South African urban communities using record linkage.

All cases of bacteriologically confirmed TB, defined as two smear-positive results and/or at least one culture-positive result, were included. Record linkage was performed between three data sources: 1) TB treatment registers, 2) the nearest central laboratory, and 3) the referral hospital laboratory.

The TB treatment registers had 435 TB cases recorded, of which 204 (47%) were bacteriologically confirmed. An additional 39 cases recorded as non-bacteriological cases in the TB treatment registers were reclassified as bacteriologically confirmed, and 63 bacteriologically confirmed cases were identified from the laboratory databases that were not recorded in the TB treatment registers. The final number of bacteriologically confirmed TB cases was 306, giving an increase of 50%.

The accuracy and completeness of the TB treatment register and central laboratory data were inadequate. A high percentage of bacteriologically confirmed cases from both laboratories were not recorded in the TB treatment registers. We are developing an electronic result management system to improve the management of laboratory results.