Measuring Self-efficacy and Outcome Expectancy in Evidence-based Practice: A Systematic Review on Psychometric Properties

Background: Evidence-based practice has developed over the last 30 years as a tool for the best possible nursing care. Nevertheless, many nurses do not regularly participate in the evidence-based practice process. Barriers to participation include nurses' self-perceived ability in successfully fulfilling evidence-based practice-related tasks (self-efficacy) and their expectations of the positive outcomes of such tasks (outcome expectancy). To evaluate progress and provide feedback to professionals, monitoring the levels of self-efficacy and outcome expectancy with validated instruments is desirable. A comprehensive overview of the psychometric properties of such instruments is lacking.

Objectives: To determine the psychometric properties of instruments designed to measure nurses' self-efficacy and outcome expectancy in evidence-based practice.

Design And Method: This systematic review was performed on studies reporting psychometric properties of instruments that measure self-efficacy and outcome expectancy in EBP. MEDLINE, EMBASE and CINAHL databases were searched up to March 2020. Studies that reported psychometric properties on eligible scales and studied nurses or other healthcare professionals were included. Psychometric properties included content validity, construct validity, reliability, and responsiveness. The COSMIN risk of bias checklist and criteria for good measurement properties were applied independently by two reviewers. This review is registered with PROSPERO (CRD42020183069).

Results: Eleven scales measuring self-efficacy or a similar construct and one scale measuring outcome expectancy were identified. The vast majority of the research focused on nurses. Internal consistency and structural validity were the most frequently reported properties, though the recommended confirmative factor analysis to verify the structural validity was rarely performed correctly. In addition, most studies that reported on construct validity did not hypothesise on the expected strength or direction of an effect before the data analysis. Responsiveness was not typically reported or was incorrectly studied. The included articles showed a high quality of evidence for four scales on structural validity and internal consistency. The Self-Efficacy in Evidence-Based Practice Activities scale showed the best content validity and was accompanied by an Outcome Expectations of Evidence-Based Practice scale. Both scales met the COSMIN standards for construct validity with high-quality evidence.

Conclusions: In light of the evidence, the Self-Efficacy in Evidence-Based Practice Activities scale is considered promising, and along with the accompanying Outcome Expectations of Evidence-Based Practice scale, appears capable of accurately measuring both self-efficacy and outcome expectancy. The use of these scales is recommended, and further research should be conducted on the responsiveness of the scales.