METHOD OF CALCULATION

Every quarter, every RNTCP district in the country reports every patient placed on treatment. The numbers correlate with the entries made in Tuberculosis Registers. As of 31 March 2001, the total number of patients who had been treated under the RNTCP was 549,611.

Patients Treated
To obtain the estimated number of patients treated on any particular day, it is assumed that the number treated in the current quarter is no less than the number treated in the previous quarter. This is a conservative assumption, since the RNTCP continues to expand, and because case detection rates are increasing.

Lives Saved
To estimate the number of lives saved, best available data from both the RNTCP and the NTP are used. A systematic evaluation of outcomes in the NTP indicated that 29% of the smear-positive patients died (Datta M, Radhamani MP, Selvaraj R, et al. Critical assessment of smear-positive pulmonary tuberculosis patients after chemotherapy under the district tuberculosis programme Tubercle and Lung Dis 1993;74:180-186). Data from the National Tuberculosis Institute, Bangalore and the Tuberculosis Research Center, Chennai suggest that approximately 10%-12% of smear-negative patients die under programme conditions in the NTP. In the RNTCP, no more than 4% of all patients die. Thus, taking a weighted average of smear-positive and smear-negative patients, the differential mortality is at least 18%. That is, for every hundred patients treated under the RNTCP, at least eighteen lives are saved.

This is, however, a conservative estimate for the following reasons:

1. As there was no short course chemotherapy previously in many areas where the RNTCP is being implemented, the differential increase in survival would be much greater.

2. It is assumed that every patient treated under the RNTCP would have been treated under the NTP. The detection rate of smear-positive patients under the RNTCP, however, is nearly twice that of the NTP. Therefore, substantially more patients who have serious tuberculosis are being accurately diagnosed and appropriately treated under the RNTCP.

3. Secondary cases, in whom tuberculosis develops because of its continued spread in areas not implementing the RNTCP, are not accounted for. Prevention of secondary cases because of higher cure rates would further increase the number of lives saved under the RNTCP.