Intensive care has been in the forefront of quality investigations. Outcomes researchers have taken advantage of reliable and robust methods to adjust for severity of illness and other case mix variables, and readily identifiable relevant outcomes (survival and death) to investigate quality factors associated with improved risk-adjusted outcomes. Current studies are limited by using databases of convenience, use of historical controls, small sample sizes, and inadequate case-mix adjustment. Only one study has focused on the comparative advantage of pediatric versus adult intensive care units for injured children; it demonstrated substantially improved risk-adjusted mortality rates. The effect of volume on quality of pediatric intensive care has been the subject of multiple evaluations, although each of these studies has serious limitations. Other studies have demonstrated that the experience of the bedside caregiver is important in patient outcomes.