Volume-outcome relationship in critical care: a systematic review

The relationship between provider volume and patient outcome has been demonstrated for many medical and surgical services, including critical care. This relationship is used as one rationale for regionalization of adult intensive care. However, the volume-outcome relationship is not always consistent across studies, and it has not been explicitly evaluated in a heterogeneous population. We performed a systematic review of studies that assessed the association between volume and outcome among critically ill adult patients.