A clue from a self-report questionnaire to distinguish rheumatoid arthritis from noninflammatory diffuse musculoskeletal pain. The P-VAS:D-ADL ratio.

A clue to distinguishing rheumatoid arthritis (RA) from noninflammatory diffuse musculoskeletal pain is described on the basis of 2 self-report questionnaire scales, one to assess difficulty in activities of daily living (D-ADL) and a pain visual analog scale (P-VAS). Patients with RA have significantly higher scores on the D-ADL scale compared with the P-VAS scale, while patients with noninflammatory diffuse musculoskeletal pain show the reciprocal pattern. Therefore, the ratio of the P-VAS:D-ADL scores differed significantly in the 2 groups. Ratios of less than 3 were seen in 67% of RA patients versus 28% of patients with noninflammatory diffuse musculoskeletal pain, while ratios greater than 5 were seen in 27% of patients with noninflammatory diffuse musculoskeletal pain, but not in any patients with RA. This simple ratio is clearly not a diagnostic test, but provides an initial approach to diagnosis in rheumatic diseases using a self-report questionnaire.