Validating a short-form strategy inventory for English as a foreign language learners: testing Oxford's strategy role flexibility theory

This study primarily validated the SILL - ELL Student Form for college EFL learners and, as a secondary aim, examined whether selected cross-loadings were consistent with Oxford's strategy role flexibility theory. Data from 509 Taiwanese college EFL learners were analyzed using theory-guided CFA, calibration–holdout cross-validation, reliability and validity analyses, and gender invariance testing. The initial six-factor simple-structure model showed inadequate fit, but a revised six-factor model fit acceptably after three items were removed, one item was reclassified, and four compensation-related cross-loadings were estimated. The resulting 25-item SILL - SEFL differed from the SILL - ELL in target population, item composition, one item classification, and the inclusion of theory-guided secondary loadings. The findings provide qualified support for Oxford's six broad strategy categories and indirect psychometric evidence consistent with strategy role flexibility; however, cross-loadings should not be interpreted as direct proof of flexible strategy use. Results support cautious use of the SILL - SEFL in comparable college EFL contexts and highlight the need for external replication.