Rate of negative conversion at 3-month, 6-month, 9-month, 12-month and 15 - 24-month period by sputum AFB smear were, in turn, 41%, 57.4%, 58.1%, 60.3%, 61% and sputum BK culture were, in turn, 28.7%, 50%, 54.4%, 57.4%, 59.6% và 61%.