Stroke self-efficacy questionnaire - Denmark (SSEQ-DK): test-retest of the Danish version

Background In stroke rehabilitation, measurement tools measuring self-efficacy with sound psychometric properties are needed. The Stroke Self-Efficacy Questionnaire (SSEQ) has recently been translated and validated into a Danish version (SSEQ-DK). Objectives To evaluate the test-retest reliability of the SSEQ-DK. Methods Fifty people with stroke >= 18 years in the sub-acute and chronic phase were included from February 2019 to August 2020. The SSEQ-DK was completed twice; on day 1 and day 7-14. Test-retest reliability of the single items was assessed using weighted Cohen's kappa and percentage agreement. The activity and self-management scales were assessed by the intraclass correlation coefficient (ICC). Measurement error was assessed by calculating the Smallest Detectable Change (SDC) based on the standard error of measurement. Results Overall, kappa values showed fair to substantial test-retest reliability of the single items. However, several kappa values were missing as the statistical prerequisites were not present. The percentage agreement ranged from 78% to 94%. Based on the reported confidence interval of the estimated intraclass correlation coefficient, the test-retest reliability of the activity and self-management scales was poor to excellent in all analysis. Ceiling effects appeared in the single items. Conversely, no floor effect was seen. Conclusion The SSEQ-DK showed good test-retest reliability of the single items based on agreement among a population with stroke in the subacute and chronic phase. Broad ICC confidence intervals bar any firm conclusions concerning the test-retest reliability of the activity and self-management scales.