Team behavior and coordination, particularly communication or team information-sharing, are critical for optimizing team performance; research in medicine generally provides no accepted method for measurement of team information-sharing. In a controlled simulator setting, we developed a technique for placing clinical information (probes) with members of a team of trainees participating in a 1-day Anesthesia Crisis Resource Management course and later tested the teams for knowledge of the probes as an indicator of overall team information-sharing. Despite the low level of team information-sharing, we demonstrated construct validity of the probe methodology by the correlation of measured change in team information-sharing from beginning to end of training with self-rated change. There was no statistical difference in "group sharing" from beginning to end of training, despite trainees' survey responses that the course would be useful for their education and practice.