Psychometric testing of an instrument measuring core competencies of nursing students: an application of Mokken scaling.

Assessing the core competencies of nursing students provides information about students' learning outcomes for educational evaluation and improvement. The aim of this study was to develop the Nursing Students Core Competencies scale to measure 8 core competencies of nursing students in Taiwan. The study employed factor analysis and Mokken scaling analysis for psychometric testing of this instrument between a group of nursing graduates and their evaluators. The results indicated that the Nursing Students Core Competencies scale has demonstrated evidence of internal consistency, structural validity, unidimensionality, and a hierarchy of items for students' self-assessment and instructor's rating. The use of Mokken scaling analysis extends the knowledge of developing competence assessment tools; it can be used to reveal the domains or items of competency nursing students perceive that are easy or difficult, providing information for curricular design.