RELATION BETWEEN DEGREE OF TUBERCULIN SENSITIVITY AND PREVALENCE OF TUBERCULOSIS.

The authors have studied the possibility of using a low-dose tuberculin test for the selection of persons for radiographic examination by analysing data from an epidemiological survey conducted in Portuguese Guinea on nearly 70 000 persons.It was found that the likelihood of a person's having pulmonary tuberculosis increased steadily with increase in size of tuberculin reaction, but also increased equally steadily with age. The authors therefore conclude that selection of persons for X-ray examination could most profitably be done by taking into account both these factors and, for instance, X-raying all persons in the oldest age-groups (45 years and over), but only the strong tuberculin reactors among the younger age-groups.