Measurement properties of the Swedish version of the Knee Self-Efficacy Scale: A Rasch analysis.
cross_sectional · Level IV
Where this comes from
- Record sourced from PubMed, PMID 40510625.
- Also identified by DOI 10.1002/jeo2.70306 and PMC identifier 12159449.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
This study aimed to evaluate measurement properties of the Swedish version of the Knee Self-Efficacy Scale 18 items version (K-SES<sub>18</sub>) in patients after anterior cruciate ligament (ACL) reconstruction using Rasch measurement theory (RMT). Data were extracted from Project ACL, a rehabilitation registry. Responses to the K-SES<sub>18</sub> from 1307 patients (aged 15-50 years) at 12 months post-ACL reconstruction were analyzed. The RMT analysis assessed targeting aspects of reliability, response category thresholds, item hierarchy, overall and individual item fit, local dependency, differential item functioning (DIF) and unidimensionality. The use of RMT indicated that the K-SES<sub>18</sub> present subscale exhibited high reliability (Person separation index = 0.904; Cronbach's <i>α</i> = 0.939) but also a potential ceiling effect (mean person location = 1.440). Disordered thresholds were observed in 11 out of 14 items, which indicates that, according to the RMT, patients might have some difficulties to distinguish between response categories. Item misfit was noted, which suggests multidimensionality. Subgroup analyses partially resolved local dependency but indicated distinct dimensions for daily activities, leisure activities and physical activities. The K-SES<sub>18</sub> future subscale also demonstrated good reliability (PSI = 0.750; <i>α</i> = 0.783) but showed targeting issues and multidimensionality across items. The main finding of this study is that the K-SES<sub>18</sub>, according to RMT, demonstrates strong reliability but has limitations in terms of measurement properties that possibly limit its clinical utility. The present and future subscales exhibit ceiling effects, disordered thresholds, and item misfit. Therefore, the K-SES<sub>18</sub> might not be able to capture the full range of patients' knee self-efficacy after ACL reconstruction. These findings indicate that a scale refinement to enhance targeting, response sensitivity, and dimensionality is needed. Clinicians are therefore advised to interpret the subscale scores cautiously, acknowledging the multidimensional nature of the constructs measured. Level III.