Physical functioning of patients with hip or knee osteoarthritis (OA) is measured by self-report questionnaires and performance-based tests. Although, performance-based tests are frequently not practical. The authors conducted this study in order to develop a computer-administered Animated Activity Questionnaire (AAQ) by showing animations of activities the influence of the patient’s own reference frame is minimised. They suspected that the AAQ measures the same aspects of physical functioning as performance-based tests do. They developed a pilot version of the AAQ using motion capture to analyze the movement of a person performing 7 daily activities. Different animations of the same activity were made with two to five levels of difficulty. For each activity, patients were asked to choose one animation that best corresponds to their own way of performing the activity. A preliminary validation study was performed in which we compared the AAQ with validated self-report questionnaires (H/KOOS and questionnaires on walking, stair climbing and rising/sitting down) and performance-based tests (walking, timed-up-and-go, timed-stair-test) in 33 patients with hip or knee OA. As suspected, the AAQ showed a correlation above 0.70 (0.79 (0.61-0.89)) with the total score of the performance-based tests. On subscore level, the results were partly as suspected. Fifty-eight percent of the patients preferred the AAQ over questionnaires and performance-based tests. They added that their findings should be replicated in larger samples of patients due to the fact that the sample size of their study was somewhat small.
The authors concluded that the AAQ could be a good alternative for gauging physical functioning of patients with hip or knee OA. The AAQ can easily be adapted for use in other patient populations. However, they felt that more development and validation is needed.