Model parameters, base case and reasonable ranges.

AFB = Acid fast bacillus; AII = airborne infection isolation; GMH = Grady Memorial Hospital, Atlanta, GA, USA; NAAT = nucleic acid amplification test; PPV = positive predictive value; TB = tuberculosis
*Base case was determined by multiplying charge by cost/charge ratio.
∧This upper bound was determined in the cited publication by considering all aspects of outpatient care in calculating treatment cost and was included for sensitivity analyses.
†We could not find estimates of exposure investigation cost in the literature, so for sensitivity analyses we took the extreme position of varying the cost from one tenth to 100 times the base case cost (for low and high bounds, respectively).
‡TB prevalence among patients in our study population, i.e. those with an AFB smear-positive sputum sample. This is equivalent to the PPV of AFB smear microscopy.
#The TB prevalence among AFB smear positives in our study (i.e. PPV of AFB smear) was lower than any found in the literature. For lower bound of TB prevalence we used PPV among HIV patients in our study, i.e. as if all AFB smear-positive patients had HIV.