Measurement properties for the revised patient-reported OsteoArthritis Quality Indicator questionnaire.
OBJECTIVES
To assess validity, reliability, responsiveness and interpretability of the revised OsteoArthritis Quality Indicator (OA-QI) questionnaire version 2 (v2) assessing patient-reported quality of osteoarthritis care.


METHODS
The OA-QI v2 (16 items, score range 0-100 (100 = best score)) was included in a longitudinal cohort study. Attendees of a 4.5 h osteoarthritis patient education programme at Diakonhjemmet Hospital, Norway, completed the OA-QI at four time points: 2 weeks before, immediately before, immediately after, and 3 months after the programme. Test-retest reliability and measurement error over a 2-week time period were assessed in those that had not seen health professionals in the interim. Construct validity and responsiveness were assessed with predefined hypotheses. Floor and ceiling effects, smallest detectable change (SDC95%) and minimal important change (MIC) were assessed to evaluate interpretability.


RESULTS
The intraclass correlation coefficient for all 16 items was 0.89. For single items the test-retest kappa estimates ranged 0.38-0.85 and percent agreement 69-92%. Construct validity was acceptable with all six predefined hypotheses confirmed. Responsiveness was acceptable with 33 of 48 and three of four predefined hypotheses confirmed for single items and all items, respectively. There were no floor or ceiling effects. The SDC95% was 29.1 and 3.0 at the individual and group levels, respectively. MIC was 20.4.


CONCLUSIONS
The OA-QI v2 had higher reliability estimates compared to v1, showed acceptable validity, and is the recommended version for future use. The results of responsiveness testing further support the use of the OA-QI v2 as an outcome measure in studies aiming to improve osteoarthritis care.
['Østerås|N|N|', 'Tveter|A T|AT|', 'Garratt|A M|AM|', 'Svinøy|O E|OE|', 'Kjeken|I|I|', 'Natvig|B|B|', 'Grotle|M|M|', 'Hagen|K B|KB|']
D005260:Female D005500:Follow-Up Studies D006801:Humans D008297:Male D008875:Middle Aged D020370:Osteoarthritis, Knee D000071066:Patient Reported Outcome Measures D011787:Quality of Health Care D011788:Quality of Life D015203:Reproducibility of Results D012189:Retrospective Studies D011795:Surveys and Questionnaires
Measurement properties Osteoarthritis Quality indicator Quality of care