School-based screening for tuberculous infection. A cost-benefit analysis

Abstract

Objective: To compare tuberculin screening of all kindergartners and high school entrants (screen-all strategy) vs screening limited to high-risk children (targeted screening).

Design: Decision, cost-effectiveness, and cost-benefit analyses.

Setting and subjects: Students in a large urban and rural county.

Definitions: High risk of tuberculosis infection was defined as birth in a county with a high prevalence of tuberculosis. Low risk was defined as birth in the United States.

Outcome measures: Tuberculosis cases prevented for 10, 000 children screened. Net costs, net cost per case prevented, benefit-cost ratio, and incremental cost-effectiveness.

Results: The screen-all strategy would prevent 14.9 cases per 10,000 children screened; targeted screening would prevent 84.9 cases per 10,000 children screened. The screen-all strategy is more costly than no screening; the benefit-cost ratio is 0.58. Targeted screening would result in a net savings; the benefit-cost ratio is 1.2. Screening all children is cost saving only if the reactor rate is 20% or greater. The cost per additional case prevented for screening all children compared with targeted screening (+34 666) is more than twice as high as treatment and contact tracing for a case of tuberculosis (+16 392).

Conclusions: Targeted screening of schoolchildren is much less costly than mass screening and is more efficient in prevention of tuberculosis.