Table 1.

Selected input parameters

Group	Parameters	California	Florida	New York	Texas
Costs	Cost inputs
Direct cost of Diagnostic tests	IGRA (Interferon gamma release assay QuantiFERON-Gold)a [28]	$85	$77	$84	$75
	Chest radiograph [29]	$22	$20	$22	$20
Direct cost of latent tuberculosis infection (LTBI) treatment	3HP (isoniazid & rifapentine, 3 months, self-administered)b [30]	$451	$404	$443	$394
	Lab testsc [28]	$41	$36	$40	$36
	Toxicity not requiring hospitalization [30]	$216	$193	$212	$189
	Toxicity requiring hospitalization [31]	$6,926	$6,208	$6,802	$6,053
Direct cost of (drug susceptible) TB treatment	Inpatient costs [32]	$42,356	$23,378	$41,685	$18,350
	Outpatient costs [33]	$3,550	$3,181	$3,486	$3,102
Cost of living adjustment	Percentage of the national average price for healthcare [15]	110.84	98.55	109.40	96.91
Effectiveness	Effectiveness inputs
Probabilities and discount rate	Probability of toxicity during LTBI treatment (without hospitalization) [11]	3.2%
	Probability of toxicity during LTBI treatment (with hospitalization) [34]	0.015%
	Probability of case fatality of TB disease [17, 30]	5.8% (9.2% for people living with HIV)
	Discount rate, per year [16]	3%
	Probability of TB hospitalization [35]	49%
QALY estimates d	Estimated quality-adjusted life years (QALY) lost per case of non-fatal TB disease (QALYs gained per TB case averted)	0.12
	Estimated QALYs lost per LTBI treatment completed [16] (probability * disutility of toxicity)	0.002

^a.Costs of additional testing among people with abnormal radiographs, such as for Mtb smear/culture, nucleic acid amplification testing, and drug susceptibility were not incorporated because these costs are not typically considered part of LTBI testing, though are part of testing persons to rule out TB disease prior to LTBI treatment.

^b.We estimated 3HP costs as $369 per patient from the healthcare system perspective excluding directly observed therapy (DOT) costs from Shepardson et al, 2013 [30] and adjusted using the Gross Domestic Product (GDP) deflator to 2018, including cost-of-living adjustment by state. Based on 1 initial clinic visit, 2 monthly follow-up clinic visits, 3 months of medication, and 12 DOT visits

^c.Lab tests include liver function test (hepatic function panel), complete blood count, and human immunodeficiency virus (HIV) testing in the first month (except for people living with HIV after HIV diagnosis). We used the lab tests cost for people living with HIV as $21.84 in California, $19.58 Florida, $21.45 in New York, and $19.09 in Texas and by excluding the HIV testing cost.

^d.Estimated results based on the QALY equation from Sassi et al. [16]