The prevalence of rheumatoid arthritis in the Sultanate of Oman.

One thousand nine hundred and twenty-five Omani adults aged 16 and over were studied in a house-to-house survey in representative areas of Oman. Seven cases (five female) are described who satisfied the 1987 ARA criteria for rheumatoid arthritis (RA), indicating a prevalence of 3.6 per thousand adults. Adjusted for the population structure, the prevalence was 8.4 per thousand adults. Complementary data are also presented on cases of RA ascertained by special screening clinics in rural health centres and by hospital rheumatology clinics. In all parts of the study, cases of RA were less often seropositive than in European populations which may account for the lower prevalence of erosive disease.