Development and testing of a computerized animated activity questionnaire (AAQ) for assessing activity limitations in patients with hip and knee osteoarthritis

Purpose: Essential in the management of hip and knee OA is a comprehensive assessment of physical functioning. The aim is to assess how patients perform their daily activities and what limitations they experience, in order to develop a treatment plan and evaluate treatment. The ideal assessment would consist of observations of a patient’s actual performance of activities in daily life, but this is not feasible. Therefore, other measurement instruments are being used; most often self-report questionnaires and performance-based tests. Self-report questionnaires and performance-based tests correlate moderately in measuring activity limitations, indicating that they measure different aspects. Self-reports measure mainly how patients think they perform an activity, and is influenced by pain, fatigue or situations they are referring to. This may lead to cross-cultural differences. Performance-based tests measure an artificial situation, is resource-intensive and burdensome for patients. We therefore intended to develop a new method, the Animated Activity Questionnaire (AAQ), which combines the advantages of self-report questionnaires and performance-based tests, without many of their disadvantages. The aim of this study was to develop a computerized Animated Activity Questionnaire (AAQ) to assess activity limitations in patients with hip/ knee osteoarthritis and preliminary testing of its validity and reliability. Methods: Based on the pilot version, International Classifications of Functioning, disability and health (ICF) core set for osteoarthritis, focus groups of patients, and existing measurement instruments, the AAQ was developed. In 954 patients from seven European countries correlations were calculated between the AAQ and self-reported Hip disability and Knee injury Osteoarthritis Outcome physical functioning score. In addition internal consistency was calculated. In 212/954 patients also correlations with performance based tests (Timed Up and Go test, Stair Climbing Test, and the 30 second Chair Stand Test) were calculated. Test-retest reliability was assessed by repeated scoring in 166/954 patients. Finally in a subgroup of 22 Dutch patients correlations were calculated between scores of the AAQ and scores of real life videos recorded activities taken at the patients’ home. Results: The Animated Activity Questionnaire (AAQ) includes animated videos of 17 basic daily activities with four levels of increasing difficulty (check the following link for two examples: http://kmin-vumc.nl/_14_0.html). Patients were asked to select the video that best matched their own performance. Cronbach’s alpha was 0.94. Correlation with self-reported physical functioning scores was high with 0.72 (95% Confidence Interval (95% CI) 0.69-0.75). A moderate correlation was seen of the AAQ mean score with Timed Up and Go test (0.67, 95% CI: 0.58-0.74), Stair Climbing Test (0.61, 95% CI: 0.52-0.69), and 30 sec Chair Stand Test (0.35, 95% CI: 023-0.47). Correlation of the AAQ mean score with pain was lower (0.53, 95% CI: 0.48-0.57) than the correlation of the self-reported physical functioning mean score with pain (0.73, 95% CI: 0.70-0.76). For test-retest reliability, an Intraclass Correlation Coëfficiënt of 0.94 (95% CI 0.92-0.95) was found. And finally, a high correlation of 0.84 (95% CI: 0.62-0.93) was found between the mean AAQ score and the mean score of the real life video recorded activities at the patients’ home. Conclusions: A computerized Animated Activity Questionnaire (AAQ) was developed showing a high internal consistency and excellent test-retest reliability. Content validity was considered good, and construct validity is supported by high correlations with self-reported physical functioning and moderate correlations with performance-based tests. The AAQ seems to be less influenced by pain compared with self-reported physical functioning and seem to measure activities limitations closely to the real life situation. Since minimal reading ability and translation is needed, the AAQ has potential for low literacy populations, non-native speakers, and international use. Continuing research will focus on construct validity and cross-cultural validity.