There have been many studies of the volume-outcome relationship. In all of these, the unit of analysis is the hospital or physician. However, this level of analysis is mostly limited to the use of in-hospital mortality rates and is particularly sensitive to selective referral. Moreover, the...

I analyze the effects of four types of medical innovation and cancer incidence on US cancer mortality rates during the period 2000–2009, by estimating difference-in-differences models using longitudinal (annual) data on ∼60 cancer sites (breast, colon, etc.). The outcome measure used is not...