A Study of Rheumatic Disease in a Canadian Indian Population.

Rheumatoid arthritis is an endemic disease known throughout the world. Its aetiology is unknown. No meaningful differences in prevalence rates between populations or races have so far been established, although Lawrence (1959) has shown a small difference in prevalence between rural and urban communities. Large geographical differences in prevalence are unlikely to have escaped detection by ordinary methods of study. The possibility remains that small but distinct differences exist between populations or races of an order which would require close statistical study for valid definition. The finding of a small but significant difference in disease prevalence between such groups would invite further study in the hope that some light might be shed on the cause or occurrence rate of the disease. Numerous reports of the prevalence ofrheumatoid arthritis have appeared in recent years. One of the most complete is that of Lawrence (1961) and his associates in Wensleydale and Leigh in Great Britain (W.-L. study). This survey of a random sample from rural and urban areas including all persons aged 15 and over serves as a useful basis for the design of a comparative study.