Background and PurposeThe objectives of this study were to develop a National Nursing Core Competency Standards (NNCCS)-based instrument and determine its construct validity and internal consistency reliability.MethodsA methodologic research design was used to validate the 59-item scale based on the responses of 600 nurses. The scale items were culled from the client care, leadership and management, and research competencies identified in the NNCCS.ResultsThe results of the analyses confirmed 53 items and gave rise to a five-factor solution. The five dimensions are leadership, management, research, ethico-legal, and strategic competencies.ConclusionsThe seminal psychometric testing provided an evidence of acceptable validity and reliability of the proposed instrument. Further testing was recommended to accrue the psychometric soundness of the instrument.