Nurses' ethical leadership and related outcome variables: Systematic review and meta‐analysis

To investigate the outcomes and the effect sizes of ethical leadership in nursing practice.Many meta-analysis of ethical leadership have been conducted in other fields, but there are none for the effects of ethical leadership of nurse leaders and should be investigated.For a systematic literature review, we searched PubMed, EMBASE, the Cochrane Library, CINAHL, OVID, Web of Science and Korean databases for studies published in Korean or English. We used Comprehensive Meta-Analysis (CMA) 2.0 and R 3.6.2 for the meta-analysis.We divided the outcomes of ethical leadership into three categories and investigated the effect sizes: subordinates' perceptions of their leaders (ES = 0.65), subordinates' ethical behaviours (ES = 0.04) and job or organisational outcomes (ES = 0.45). In addition, we identified 14 outcome variables, and transformational leadership showed the greatest effect size (ES = 0.77) among them.This study confirmed the positive effects of ethical nursing leadership on individual nurses' perceptions about their leaders, their jobs and organisations.Nursing organisations and nurse administrators should make efforts to highlight ethical leadership of nurse leaders to improve outcomes of organisational performance including individual nurses' perceptions about their leaders, their jobs and organisations.