A validation study using a modified version of Postural Assessment Scale for Stroke Patients: Postural Stroke Study in Gothenburg (POSTGOT).

Background: A modified version of Postural Assessment Scale for Stroke Patients (PASS) was created with some changes in the description of the items and clarifications in the manual (e.g. much help was defined as support from 2 persons). The aim of this validation study was to assess intrarater and interrater reliability using this modified version of PASS, at a stroke unit, for patients in the acute phase after their first event of stroke.
Methods: In the intrarater reliability study 114 patients and in the interrater reliability study 15 patients were examined twice with the test within one to 24 hours in the first week after stroke. Spearman's rank correlation, Kappa coefficients, Percentage Agreement and the newer rank-invariant methods; Relative Position, Relative Concentration and Relative rank Variance were used for the statistical analysis.
Results: For the intrarater reliability Spearman's rank correlations were 0.88-0.98 and k were 0.70-0.93 for the individual items. Small, statistically significant, differences were found for two items regarding Relative Position and for one item regarding Relative Concentration. There was no Relative rank Variance for any single item.For the interrater reliability, Spearman's rank correlations were 0.77-0.99 for individual items. For some items there was a possible, even if not proved, reliability problem regarding Relative Position and Relative Concentration. There was no Relative rank Variance for the single items, except for a small Relative rank Variance for one item.
Conclusions: The high intrarater and interrater reliability shown for the modified Postural Assessment Scale for Stroke Patients, the Swedish version of Postural Assessment Scale for Stroke Patients, with traditional and newer statistical analyses, particularly for assessments performed by the same rater, support the use of the Swedish version of Postural Assessment Scale for Stroke Patients, in the acute stage after stroke both in clinical and research settings. In addition, the Swedish version of Postural Assessment Scale for Stroke Patients was easy to apply and fast to administer in clinic.