THE TUBERCULIN TEST.

A brief historical review of the tuberculin test is followed by consideration of the immunological factors concerned in the tuberculin reaction. The problems in the interpretation of the test, the dosage and types of material used, and methods of administration are discussed. The current problem of tuberculin reversion with and without treatment, as exemplified by the current study of Halifax school children, is considered in some detail. The role of the tuberculin test in the present-day program of tuberculosis control is indicated.