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

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.