To provide metrics for quantifying the capability of hospitals and the degree of care regionalization.
Administrative database covering more than 10 million hospital encounters during a 3‐year period (2012–2014) in Massachusetts.
We calculated the condition‐specific probabilities of transfer for all acute care hospitals in Massachusetts and devised two new metrics, the Hospital Capability Index () and the Regionalization Index (), for analyzing hospital systems. The had face validity, accurately differentiating academic, teaching, and community hospitals of varying size. Individual hospital capabilities were clearly revealed in “fingerprints” of their condition‐specific transfer behavior. The also performed well, with those of specific conditions successfully quantifying the concentration of care arising from regulatory and public health activity. The median of all conditions within the Massachusetts health care system was 0.21 (, 0.13–0.36), with a long tail of conditions that were very highly regionalized. Application of the and metrics together across the entire state identified the degree of interdependence among its hospitals.
Condition‐specific transfer activity, as captured in the and , provides quantitative measures of hospital capability and regionalization of care.