TABLE 3.

The effect of Xpert Ultra trace call result interpretation on Xpert Ultra diagnostic accuracy for TB and TB treatment recommendations

	Sensitivity		Specificity		Number recommended for TB therapy based on Ultra result (yield)
	n/N	% (95% CI)	n/N	% (95% CI)
Ultra Trace call result considered negative (all considered negative)
All	73/92	79.3 (69.6–87.1)	643/648	99.2 (98.2–99.7)	78
Smear-positive	45/46	97.8 (88.5–99.9)	1/2	50.0 (1.26–98.7)	46
Smear-negative	28/46	60.9 (45.4–74.9)	641/645	99.4 (98.4–99.8)	32
Ultra Trace call result considered positive (according to original WHO guidance)*
All	74/92	80.8 (70.9–88.0)	627/648	96.8 (95.1–98.0)	95
Smear-positive	45/46	97.8 (86.0–99.5)	1/2	50.0 (1.3–98.7)	46
Smear-negative	29/46	63.0 (47.5–76.8)	625/645	96.9 (95.3–98.1)	49
Ultra Trace call result considered positive (according to current WHO guidance)†
All	76/92	82.6 (73.3–89.7)	611/648	94.3 (92.2–95.9)	113
Smear-positive	45/46	97.8 (88.5–99.9)	1/2	50.0 (1.3–98.7)	46
Smear-negative	31/46	67.4 (52.0–80.5)	609/645	94.5 (92.4–96.1)	67
Ultra Trace call result considered positive (all considered positive)
All	76/92	82.6 (73.3–89.7)	608/647	94.0 (91.9–95.7)	115
Smear-positive	45/46	97.9 (88.5–99.9)	1/2	50.0 (1.3–98.7)	46
Smear-negative	31/46	67.4 (52.0–80.5)	607/645	94.1 (92.0–95.8)	69

^*Trace call result considered a true positive result for HIV-positive persons and a false-positive result for HIV-negative persons.

^†Trace call result considered a true-positive result for HIV-positive persons and HIV-negative persons not previously treated for TB and a false-positive result for HIV-negative persons with a prior history of TB.

CI = confidence interval.