Since the publication of Hamburger and Monti's1 report in 1909, there has been considerable interest and study in the estimation of the incidence of tuberculous infection in children in various parts of the world. Until recent years, most of the data available have been compiled from urban clinics. In a careful search through the literature for data representative of rural districts, there were found studies by Slater2 in Minnesota, Baker3 in Alberta, Ferguson4 in Saskatchewan and Vories5 at the Mayo Clinic. There being considerable variation in the results reported it seemed that it would be of interest to compare the data herewith presented with these studies as well as with some from urban centers.
The data has been collected from the records of patients treated in the pediatric division of Children's Hospital, Iowa City. The children are preponderantly of the indigent class. Although they are