Barriers to reporting medication errors: a measurement equivalence perspective.

OBJECTIVES To demonstrate a statistical analysis for testing the measurement equivalence of a patient safety survey instrument. The survey instrument examined in the present study is the Medication Administration Error Reporting Survey. METHODS Surveys were posted to a random sample of registered nurses in the State of Texas, with 435 nurses completing the survey. The surveys contained questions about various error reporting issues, including the 16-item, Medication Administration Error Reporting scale. Nurses were divided into one of two samples--calibration and holdout--to ensure replicability of the results. Within each sample, two groups were created based on nurse tenure on the job. RESULTS Multiple Group Confirmatory Factor Analysis was conducted across nurses with varying levels of experience for the calibration and holdout samples. For each sample, a baseline model was estimated, where model parameters were allowed to vary across the nursing groups, and compared with more restrictive models. The results provided support for the factor structure of the Medication Administration Error Reporting System but yielded mixed results concerning the equivalence of the measure across nursing groups. CONCLUSIONS The present study provides an explanation of how to examine the measurement equivalence of survey instruments and demonstrated that the Medication Administration Error Reporting scale might not be equivalent across nurses who differ with respect to experience levels.