The Establishment and Examination of the Reliability, Validity, Discrimination, and Difficulty of Nursing Objective Structured Clinical Examination (OSCE)

Abstract

The objective structured clinical examination (OSCE) is one of the evaluation strategies used to examine the clinical competence of nursing students. More attention needs to be paid to establishing an examination that is based on the standardized protocol and on reliability and validity. The aims of this study were to develop an OSCE that is based on a standardized protocol and to analyze the content validity and predictive validity, inter-rater consistency, internal consistency, item-to-total correlation, and the degree of discrimination and difficulty of this OSCE. Based on the blueprint for OSCEs that use an 8-station format, this study used a descriptive, cross-sectional design and a sample population of 207 senior students who were preparing for their last-mile practicum at a nursing technology university in northern Taiwan. The study period lasted from September 2015 to October 2016. Furthermore, the validity, reliability, degree of discrimination, and difficulty of the OSCE were examined. An OSCE with an eight-station format was developed. The content validity index (CVI) was .85-1.0, inter-rater reliability was .80-1.0, Cronbach' alpha internal consistency was .53-.82, and item-to-total correlation was .36-.63. In addition, the level of difficulty of the OSCE was easy to moderate and the discrimination of the OSCE ranged from fair to excellent. Meanwhile, the OSCE scores of the participants appeared to be a valid predictor of scores on the last mile practicum. According to the standardized protocol of OSCE development, an 8- station nursing OSCE format is reliable and valid, providing fair levels of difficulty and discrimination. The developed OSCE may be applied to evaluate the clinical competence of nursing students prior to beginning their last mile practicum. The results from the present study may provide a reference for nursing educators who are responsible for developing OSCE evaluation strategies.