For developing an appropriate strategy for combating tuberculosis in the country, it is necessary to obtain a precise estimate of the disease in the community. The process of estimating it for as large and diverse a country as India is not only difficult, but is also expensive and time consuming. It is common knowledge that the nation wide sample survey carried out by the Indian Council of Medical Research (ICMR) in 1955-58 (NSS), followed by several similar surveys conducted at the National Tuberculosis Institute, Bangalore (NTI), New Delhi Tuberculosis Centre and the Tuberculosis Research Centre, Chennai (TRC) had provided the basis.
