Epidemiology of sarcoidosis in the Isle of Man--2: Evidence for space-time clustering.

The case-control test for space-time clustering developed by Pike and Smith was applied to 96 cases of sarcoidosis diagnosed in the Isle of Man from 1962 to 1983. There were significantly more links between cases separated by time intervals of less than 10 years and distances of less than 100 metres than between the others. Analysis of the type of links indicated that clusters consisted of pairs whose contact was by place of residence or work. More linked cases were diagnosed less than three years apart than would be expected by chance. These findings lend support to the idea that sarcoidosis is a communicable disease.