SELF-LEADERSHIP: A META-ANALYTIC REVIEW OF INTERVENTION EFFECTS ON LEADERS' CAPACITIES

Leadership interventions are increasingly popular, but their effects on self-leadership of leaders are largely unknown. The objective of the current study was to evaluate benefits of leadership interventions on leaders' self-leadership capacities. The search encompassed studies published between 1986 and 2019. Included were randomized controlled trials (RCTs), controlled before-and-after studies (CBA), before-after studies without controls (BA), case studies, and qualitative longitudinal studies that examined potential effects of interventions on leaders' self-leadership capacities. Primary outcomes attributable to self-leadership theory and its strategies measured by validated instruments were extracted. A meta-analysis was conducted for quantitative controlled studies with comparable primary outcomes. Eleven studies fulfilled the inclusion criteria, with a total of 571 participants in leadership positions. Eight quantitative studies, two RCT studies, four quasi-experimental field studies with a pre-post design (CBA), and two intervention case studies (BA), were included. Three qualitative studies evaluated a comparable form of leadership development. All studies showed positive but small to medium-sized effects of leadership training on primary outcomes. Results of the review contribute to knowledge of the effectiveness of training for self-leadership capacities of leaders and identified gaps where evidence remains limited. The findings tentatively suggest that leadership interventions could be beneficial for developing self-leadership skills. Future studies should focus on content, frequency, and intensity of interventions. Mixed methods are strongly recommended.