Quality of life of people with rheumatoid arthritis as measured by the World Health Organization Quality of Life Instrument, short form (WHOQOL-BREF): score distributions and psychometric properties

OBJECTIVE: To assess the psychometric properties, including responsiveness, of the World Health Organization Quality of Life instrument, short form (WHOQOL-BREF) in people with rheumatoid arthritis.METHODS: A sample of 142 persons with rheumatoid arthritis were randomly selected from a regional disease register and completed questionnaires by postal survey. An additional sample of 72 consecutive inpatients completed questionnaires a few days prior to admission, the day of admission, the day of discharge, and 2 weeks following discharge.RESULTS: Test-retest reliability was adequate (intraclass correlation coefficient 0.71-0.91). Internal consistency was adequate except for the social relationships domain (Cronbach's alpha 0.64-0.87). Factor structure was fairly similar to that previously reported. Correlation with other measures of quality of life was supportive of concurrent validity. Indices of responsiveness were satisfactory except for the social relationships and environment domains, although there was actually no statistical difference in the area under a receiver operating characteristic plot between the WHOQOL-BREF domains and the Health Assessment Questionnaire.CONCLUSION: The WHOQOL-BREF has adequate psychometric properties in people with rheumatoid arthritis and should be considered a valid outcome measure for interventions that aim to improve quality of life for people with this disease