Table 1.

Test characteristics for new TB diagnostics set by the world health organization.

Use case	Goal of the test	Potential applications	Characteristics	Optimum	Minimum
Triage	To identify individuals who need a confirmatory test or those who are unlikely to have TB	•Systematic TB screening in community settings. •Ruling out active TB before TB preventive treatment	Sensitivity	> 95%	> 90%
			Specificity	> 80%	> 70%
			Cost	< US$ 1.00/ test	< US$ 2.00/ test
Diagnosis	To diagnose both pulmonary and extrapulmonary TB using non-sputum samples for the purpose of initiating treatment	•Diagnosis of TB and treatment initiation on the same day by health workers with limited training in peripheral facilities	Sensitivity for pulmonary TB in adults	≥ 98% for smear-positive culture-positive pulmonary TB ≥ 68% for smear-negative culture-positive pulmonary TB	Overall sensitivity should be ≥ 65% but should be > 98% among patients with smear-positive culture-positive pulmonary
			Sensitivity for extrapulmonary TB in adults	>=80%	No lower range of sensitivity defined
			Sensitivity in children	>= 66%	No lower range of sensitivity defined
			Specificity	>= 98%
			Cost	< US$ 4.00/ test	< US$ 6.00/ test
Prediction for progression to active TB	To identify people who develop active TB and thus benefit from TB preventive treatment	•To identify individuals with or without risk factors who are at risk for TB development and should be given TB preventive treatment	Sensitivity for progression to active TB in 2 years	>=90%	>=75%
			Specificity for progression to active TB in 2 years	>=90%	>=75%
			Cost	< US$ 5.00/ test	< US$ 10.0-100/ test
Monitoring treatment response	To identify people who are not cured and at risk for relapse.	•Individualise treatment duration •Evaluate the efficacy of new drugs quickly.	No target product profile is available

Note: We focused on the performance of the tests and costs, which are considered critical attributes of the tests. See full target product profiles and explanations in WHO reports.^10,29