Causality is essential in informing science and policy. In the present study, we investigate the current state of research regarding causality in the field of servant (and authentic) leadership and provide recommendations on how causally identified studies can be conducted. After explaining the methodological problems that potentially prevent causal inferences (i.e., endogeneity bias and issues in experimental design), we provide two systematic literature reviews of servant and authentic leadership showing that these problems remain very prevalent. We then discuss two solutions on how causal effects of servant leadership or perceptions thereof can be established: randomized experiments and instrumental variable regression. To illustrate our recommendations, we report an experiment on the effect of a combination of two servant leadership dimensions (i.e., stewardship and authenticity) on follower performance and also investigate the effect of combined stewardship and authenticity perceptions using instrumental variable regression. The results do not indicate that combined stewardship and authenticity behavior or perceptions affect follower performance. Our study can serve as a roadmap, especially for servant leadership researchers, to address potential endogeneity and conduct causally identified research.

因果关系对于为科学和政策提供信息至关重要。在本研究中，我们调查了仆人式（和真实的）领导领域因果关系的研究现状，并就如何进行因果识别研究提供了建议。在解释了可能妨碍因果推断的方法论问题（即内生性偏差和实验设计中的问题）之后，我们提供了两篇关于仆人式领导和真实领导的系统文献综述，表明这些问题仍然非常普遍。然后，我们讨论了关于如何建立仆人式领导的因果效应或其认知的两种解决方案：随机实验和工具变量回归。为了说明我们的建议，我们报告了一项关于两个仆人式领导维度（即管理性和真实性）组合对追随者绩效的影响的实验，并使用工具变量回归研究了管理性和真实性感知相结合的影响。结果并不表明管理和真实性行为或认知的结合会影响追随者的表现。我们的研究可以作为一个路线图，特别是对于仆人式领导研究人员来说，解决潜在的内生性并进行因果识别的研究。