Test-retest reliability of the Participation domain of the Stroke Impact Scale in persons with chronic stroke

Objective: To evaluate the test-retest reliability and variability of the Participation domain of the Stroke Impact Scale (SIS Participation) in persons with stroke as it is widely used to assess perceived participation in rehabilitation after stroke. Design: A test-retest design. Subjects: Forty-five persons (mean age 65 years) with mild to moderate disability at least 6 months post-stroke. Methods: The SIS Participation domain was rated on 2 occasions, 1 week apart. The test-retest reliability of the total score was evaluated using Kappa statistics. The 8 item scores were evaluated by the proportion of participants who rated the same score (percentage agreement, PA) or ± 1 point (PA ≤ 1 point) at T1 and T2. The Svensson method was used to evaluate systematic and random disagreement. Results: The test-retest reliability of the total score showed excellent agreement (Kappa coefficient = 0.79). The items showed high PA ≤ 1 point (> 82%). No items, except 2, showed a systematic disagreement, and no items showed a random disagreement according to the Svensson method. Conclusion: The SIS Participation domain is reliable in persons with chronic stroke and mild to moderate disability and can be used to assess perceived participation in this population.