Development and Testing of an Instrument for Summative Assessment of Practical Skill Performance: A Generalizability Theory Approach

Background and Purpose: Many newly graduated nurses lack proficiency in practical skill performance. Presently, nursing students’ practical skill is assessed by summative instruments with overarching items. The purpose of this study was to develop a more detailed instrument to use in summative assessment of nursing students’ practical skill performance and to assess its psychometric properties. Methods: A 50-item instrument was developed. Video-recorded performances were rated by experienced clinical supervisors. A multifacet measurement design was developed. Relevant parameters were estimated by generalizability analysis. Results: Findings indicated that error of measurement were mainly caused by raters far more than by items. Conclusions: The present study suggested that summative assessment in realistic settings may not apply one rater only. Two to three/four raters appear necessary to dependably measure most skills