Apropos of the present level of epidemiologic knowledge on sarcoidosis.

Some particularities of the public health service in the GDR especially: 1) systematic unselected chest X-ray screening of the total population since 1954, 2) compulsory registration of sarcoidosis since 1961, 3) uniform, easily accessible and well developed medical care for all citizens represent the unique prerequisites for providing unbiased epidemiologic data in sarcoidosis. The author made use of the totally ascertained sarcoidosis population derived from the mass experiment as mentioned above and carried out an analytic study (cohort analysis of incident cases (n = 1575) adjusted for several variables. The incidence is the only parameter which is suitable for valuating the epidemiologic situation. The incidence/year ranged from 8.1 to 10.2/100,000 for a long period. Excessive ascertainment of the asymptomatic and transient forms does not contribute to the improvement of the medical care of the diseased persons. There is no reason to suppose an increase of the disease in the last 25 years. Recently the incidence curve is parallelly decreasing to the advanced restriction of the X-ray screening. Further relevant results are reviewed and some conclusions were drawn.