Do more heads imply better performance? An empirical study of team thought leaders' impact on scientific team performance

Thought leadership plays a crucial role in boosting team performance; thus, teams with more thought leaders may perform better. However, the impact of the number of thought leaders on team performance in a scientific context remains understudied. In this study, we consider the authors of a publication as a scientific team and define the authors responsible for conceptual tasks, i.e., "conceived and designed the experiments" (one of the tasks described in the PLOS contribution statements classification system), as thought leaders. Leveraging more than 140,000 papers from PLOS journals, we examine the relationship between the number of thought leaders and two aspects of team performance (i.e., team impact and team disruptiveness) from both correlational and causal perspectives. The results showed that (1) an inverted U-shaped relationship exists between the number of thought leaders and the team's impact, and (2) teams with more thought leaders tend to produce less disruptive ideas. We also explored the impact of international collaboration, team size, and gender diversity together with the number of thought leaders on team performance and found that (3) international collaboration improves team impact but lowers the disruptiveness of team outputs. This study advances scholarly understanding of thought leadership in scientific teams and provides valuable insights for policymakers and team managers.