Nurses are the most important health care personnel for medication safety. A scale to measure nurse medication competency, such as the Medication Safety Competence Scale (MSCS), would move research forward. Preliminary items were developed through a literature review and in-depth interviews. Content validity was established by ten experts. Nurses (n = 607) participated in a survey to evaluate the validity and reliability of the scale. Exploratory and confirmatory factor analyses and correlation analyses were conducted to assess construct, concurrent, and criterion validity. The 36 items and 6 factors were derived with the exploratory factor analysis, which accounted for 63.2% of the variance. The confirmatory factor analysis revealed that the hypothesized factor structure was a good fit. Criterion and discriminant validity were present. The internal consistency of the MSCS was .97, and the test-retest reliability was .78. The MSCS is a valid and reliable instrument to measure nurses' medication safety competence.
Keywords: clinical competence; medication; nurse’s role; patient safety; questionnaire design; scale development.