Yield of pulmonary tuberculosis cases by employing two screening methods in a community survey.

OBJECTIVE

To compare the yield of tuberculosis (TB) cases by two screening methods.

SETTING

Two disease surveys conducted in Tiruvallur, south India.

RESULTS

Of bacteriologically confirmed cases, 60% were identified by symptom inquiry alone whereas 82% were identified using chest radiography (CXR).

CONCLUSION

The prevalence of TB was underestimated by both methods. The total cases in this community can be estimated by multiplying the number of identified cases by a correction factor (CF) of 1.7 when symptom inquiry alone is used or 1.2 when CXR is used. The CF may be different in other settings.