Rheumatoid arthritis and spondyloarthropathies: geographical variations in prevalence in France.

Objective: To determine geographical variation in the prevalence of rheumatoid arthritis (RA) and spondyloarthropathies (SpA) in France.

Methods: The survey sample was drawn from 7 areas of France. Households were randomly selected using the national telephone directory, and an individual within each household was randomly chosen by the next-birthday method.