Impairment measures in rheumatic disorders for rehabilitation medicine and allied health care: a systematic review.

The objective of this study is to provide a critical overview of available instruments to assess impairments in patients with rheumatic disorders, and to recommend reliable and valid instruments for use in allied health care and rehabilitation medicine. A computer-aided literature search (1982-2004) in several databases was performed to identify studies focusing on the clinimetric properties of instruments designed to assess impairments in function in patients with rheumatic disorders. Data on intra-rater reliability, inter-rater reliability and construct validity were extracted in a standardized way. Explicit criteria were applied for reliability and validity. Results: The search identified a total of 49 instruments to assess impairments in functions in patients with rheumatic disorders; 19 met the criteria for reliability, 22 met the criteria for validity, and 11 out of the 49 appeared to meet the criteria for both reliability and validity. In summary, evidence of both reliability and validity was only found for 11 out of 49 instruments for the assessment of impairments in patients with rheumatic disorders. Only a limited number of the identified instruments for the assessment of impairments is both reliable and valid. Allied health care professionals should be cautious in the selection of measurement instruments to assess their patients