Developing a Short Form of the Postural Assessment Scale for people with Stroke.

OBJECTIVE To develop a Short Form of Postural Assessment Scale for Stroke patients (SFPASS) with sound psychometric properties (including reliability, validity, and responsiveness). METHODS This study consisted of 2 parts: developing the SFPASS and cross-validation. In the 1st part, 287 people with stroke were evaluated with the PASS at 14- and 30-day post-stroke intervals. The authors reduced the number of test items that constitute the PASS by more than half (i.e., making 5-, 6-, and 7-item sets) and simplified the scoring system (i.e., collapsing the 4-level scale in the original PASS into a 3-level scale [PASS-3L]), making both 4-L and 3-L versions available. Thus, a total of 6 SFPASSs were generated. In addition, 2 external criteria, the Barthel activities of daily living index and the Fugl-Meyer motor test, were used to examine the validity of the 6 SFPASSs. The psychometric properties of the new 6 SFPASSs were compared with each other as well as with those of the original PASS to determine which scale outperformed the others. In the 2nd part of the study, the authors cross-validated the best SFPASS using another independent sample of 179 people with stroke. RESULTS All 6 SFPASSs demonstrated good reliability, validity, and responsiveness. However, the Bland-Altman plots showed that only the 5-item PASS-3L demonstrated no systematic trend between the difference and mean score of the 5-item PASS-3L and the original PASS. The 5-item PASS-3L also had psychometric properties similar to those of the original PASS, as demonstrated in a cross-validation sample. CONCLUSION The authors' results provide strong evidence that the 5-item PASS-3L has sound psycho-metric properties in people with stroke. The 5-item PASS-3L is simple and fast to administer and is thus recommended.