Transactive Memory Systems and Hospital Trauma Team Performance: Shared Experience in Action Teams.

We identify and test a theoretical mechanism linking shared team experience and team performance: a transactive memory system (TMS). Our empirical context is the care of patients with severe acute traumatic injury in a hospital emergency department. We coded behavioral indicators of transactive memory from video recordings of trauma resuscitations in a hospital emergency department. We obtained objective measures of team performance -- patient lengths of stay in the intensive care unit and in the hospital -- from hospital records, as well as information about the experience of team members. Our results of analyzing data from 121patients reveal that patients treated by trauma teams with strong TMS experience significantly shorter lengths of stay in the ICU and in the hospital than patients treated by trauma teams with weaker TMS. The magnitude of the effects was large: increasing TMS by one standard deviation was associated with a reduction in hospital length of stay of 3.3 days and a reduction in ICU length of stay of 1.9 days. Experience working together predicted the strength of the team's transactive memory over and above the effect of individual experience. Further, transactive memory mediated or explained the effect of team experience on team performance. These results were robust to multiple sensitivity analyses in which we varied our definition of team experience and our modeling approach and included controls for team, task and context characteristics. We discuss the implications of these findings for strengthening TMS in trauma resuscitation teams and for theories on transactive memory and organizational learning.