Team-based learning is recognized as an important opportunity for teamwork skill development, experiential learning, and learning from peers. However, team-based learning presents many challenges. One important challenge involves the accurate, reliable and valid assessment of team health. With such diagnostics, students could receive formative feedback and engage in meaningful goal setting, adjustment and action planning. Moreover, instructors could identify teams in distress and in need of support. We examine the team CARE assessment, which is a team diagnostic on ITPmetrics.com that assesses communication, adaptability, relationships and education/learning. Although the team CARE assessment has been used extensively in educational contexts, the assessment is lengthy and time-consuming to complete. We offer a shorter version, that we call the Bare CARE assessment, by utilizing psychometric analyses and content validity to eliminate the least useful items. We find that the Bare CARE is reliable and valid when considering correlations with teamwork variables and team performance (i.e. grades). Our sample of 61,549 students working in 14,601 teams offers state-of-the-art validation evidence using a large sample that ensures stable and robust results. We discuss the implications for use in pedagogy and future research.