Rheumatoid Factor in Iceland: A Population Study

Allandor, E. (Dept. of Social Medicine, Karolinska Institute, Stockholm, Sweden), Björnsson, 0. J., Kolbeinsson,A., Olafsson, 6., SigfCisson, N., and Thorsteinsson, J. Rheumatoid factor in Iceland: a population study ,int. J. Epid. 1972,1: 211–223. In 1967–69 a study of the prevalence of rheumatoid factor (RF) was conducted in Iceland. The population surveyed was one third of each of 16 age groups of males and females in the age interval 34–61 years. The response was about 75 per cent. Each serum was tested with two RF-tests, the Rose-Waaler Test (RW) and the Acryl Fixation Test (AFT). All control-sera were compared to an international reference preparation of RF-sera. Of 1, 976 male-sera 17 were RW-positive and 17 were AFT-positive. 2, 321 female-sera were tested of which 36 were RW-positive and 30 AFT-positive (i.e. titre ≥ 1: 20).