Results of external quality assurance for microscopy.

Table 3 shows results of Ziehl-Neelsen microscopy conducted at CHR and corresponding results of EQA conducted at INH and DITM during the initial (phase I, September 2010 through December 2010) and transitional (phase II, January 2011 through April 2012) phases. N/A, not applicable.aSwab, slides were prepared as direct smears from swab samples.bFNA, slides were prepared as direct smears from fine-needle aspirate samples.cPositivity rate, number of positive samples divided by the total number of samples tested.dRate of false negative results at CHR and INH, respectively, compared to DITM results.eRate of false positive results at CHR and INH, respectively, compared to DITM results.fRate of false negative and false positive results at CHR and INH, respectively, compared to DITM results.gRate of concordant results between CHR/INH, CHR/DITM and INH/DITM.hConfirmation rate, number of laboratory confirmed BUD patients divided by the total number of suspected BUD cases.