Development of a foot impact scale for rheumatoid arthritis

Arthritis Rheum. 2005 Jun 15;53(3):418-22. doi: 10.1002/art.21176.


Objective: To develop a new foot impact scale to assess foot status in rheumatoid arthritis (RA) using established qualitative methodology and the latest item response techniques (Rasch analysis).

Methods: Foot problems in RA were explored by conducting qualitative interviews that were then used to generate items for a new foot impact scale. Further validation was undertaken following postal surveys and Rasch analysis.

Results: Analysis of the first postal survey (n = 192 responses) produced a 63-item binary response, 4-subscale instrument. The 4 subscales covered the domains impairment, activities, participation, and footwear. Following test-retest postal surveys and additional analysis, the instrument was reduced to a 2 subscale, 51-item questionnaire covering the domains of impairments/shoes and activities/participation. Initial results of these subscales indicate good psychometric properties, external validity, and test-retest reliability.

Conclusion: A foot impact scale to assess the impact of RA and to measure the effect of interventions has been developed. The 2 scales comprising the instrument demonstrate good psychometric properties.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Arthritis, Rheumatoid / physiopathology*
  • Data Collection
  • Female
  • Foot / physiopathology*
  • Humans
  • Interviews as Topic
  • Male
  • Middle Aged
  • Psychometrics
  • Shoes