The case histories of 5394 subjects who were registered in a number of Moscow. Tuberculosis Dispensaries during 1976-1988 were studied. These subjects belonged to groups III-VII and were earlier struck off the register. In Formation of groups III-VII of dispensary registry, there is an early establishment of the clinical recovery of pulmonary tuberculosis, therefore the patients with an uncured or progressive process are included in these groups. Reactivation of actually cured tuberculosis was found only in 70.7% of the subjects and the rest had an active process which has been misinterpreted as cured or as hyperdiagnosed reactivation. The main causes of the early establishment of clinical recovery, failure to establish the onset of reactivation and its hyperdiagnosis were the inadequate examination of X-ray positive subjects before their enrollment in III-VII groups, during follow-ups and striking-off, as well as errors in dispensary tactics, i. e. inadequate pre-enrollment in the O-group and diagnostic treatment. Tests for M. tuberculosis by repeated inoculation and tomography should be used in all cases in establishing clinical cure, forming Groups III-VII, following up the patients, and striking off.