Comparison between self-report measures and clinical observations of functional disability in ankylosing spondylitis, rheumatoid arthritis and fibromyalgia

J Rheumatol. 1994 May;21(5):818-23.

Abstract

Objective: To study concordance between self-report measures and clinical observations of functional disability in ankylosing spondylitis (AS), rheumatoid arthritis (RA), and fibromyalgia (FM).

Methods: 35 patients with AS completed 9 selected items of the Functional Index questionnaire, whereas 12 patients with RA and 13 with FM completed 7 selected items of the Arthritis Impact Measurement Scales. Five days later, all 60 patients and 4 controls actually performed the selected activities, which were recorded on video. The tapes were assessed in random order by 12 observers (6 occupational therapists and 6 physicians). Both patients and observers indicated functional disability on a 10 cm visual analog scale (VAS).

Results: Interobserver agreement was high (Cronbach's alpha 0.98). All observers scored the 4 healthy controls as having no disability at all. Mean discordance scores (VAS patients minus VAS observers) for the selected items were negligible in AS [-0.17 cm (p = 0.30)], moderate in RA [+1.10 cm (p = 0.06)] and high in FM [+2.44 cm (p < 0.01)].

Conclusion: Discordance between self-report questionnaires and observed functional disability is a feature most striking in FM. In validation of self-report questionnaires of functional disability the appropriate spectrum of rheumatological diagnoses should be considered.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Arthritis, Rheumatoid / physiopathology*
  • Disability Evaluation*
  • Female
  • Fibromyalgia / physiopathology*
  • Health Personnel
  • Humans
  • Male
  • Middle Aged
  • Observer Variation
  • Patients
  • Reproducibility of Results
  • Severity of Illness Index
  • Spondylitis, Ankylosing / physiopathology*