Background Leadership plays a crucial role in teams working in complex environments, and research has shown that shared leadership where all team members perform leadership functions is an effective strategy. The authors aimed to describe shared leadership patterns during anaesthesia induction and show how they are linked to team performance.

Methods 12 anaesthesia teams consisting of one resident and one nurse during a simulated anaesthesia induction including a non-routine event (asystole) were videotaped, and two kinds of leadership behaviour (content-oriented and structuring) were coded. Team performance was operationalised as the reaction time to the non-routine event. The amount of leadership sharedness was compared between low- and high-performing teams by performing a univariate analysis of variance. Wilcoxon signed-rank tests were used to analyse the distribution of the two kinds of leadership behaviour among team members.

Results Statistical analysis revealed that in high-performing teams, residents and nurses shared their leadership, while in low-performing teams, residents showed significantly higher levels of leadership behaviour than nurses. Further analyses revealed different distributions of leadership functions among team members. While residents of low-performing teams assumed both kinds of leadership behaviour, members of high-performing teams seemed to have distinct leadership roles: nurses mainly used content-oriented leadership behaviour, and residents tended to show structuring leadership behaviour.

Conclusions The study documents the effectiveness of shared leadership in situations with high task complexity and indicates that a clear distribution of content-oriented and structuring leadership among team members is an effective strategy. The findings have implications for training in shared leadership and also give rise to a number of recommendations for further research.

ClinicalTrials (http://www.clinicaltrials.gov) registration number is NCT00706108.