[Standardization of roentgenologic studies in chronic polyarthritis for therapeutic studies]

For multicenter therapeutic studies of rheumatoid arthritis (chronic polyarthritis, RA), radiological criteria for RA have been set up by a working group of rheumatologists and radiologists: the result is a radiological index for RA. For the special therapeutic studies planned, only those patients with RA should be included who have manifestations of the disease in their hands and/or feet. Radiological control at yearly intervals will show the progression of the disease by increases in radiological index values. All X-rays should be taken in the standard position and by the standard procedure, on films without intensifying screens. For exposure and quality control a metacarpal bone embedded in paraffin should be interposed between the hands or feet during radiography. Reading and interpretation of radiographs should be controlled by a second observer uninformed as to the patient and stage of disease.