1 A focus of care provision can be a disease, specialty or treatment modality where sufficient evidence based medicine metrics exist to assess quality of care.
2 Overall illness burden is based on a count of Ambulatory Diagnostic Groups (ADGs) in the base year of observation and derived from an algorithm described by Weiner et al (1991). Catastrophic shock is a concurrent year variable based on the presence of an ADG where the patient had a major acute care event, cancer diagnosis, injury or trauma.
3 No provider rating is associated with providers where there was insufficient data available for scoring or where a provider did not meet the criteria for any star rating.
4 We chose to weight by allowed charges because our interest is in the effect of the star system on resource use. This is best measured by allowed charges, some of which will be paid by the member and some by the plan.