A Harvard Medical School study in the most recent Journal of the American Medical Association shows that patients who switched to high-deductible health plans (HDHPs) visited the ER about 10% less overall than those in traditional health plans.

The study also showed a specific 25% reduction in repeat ER visits for non-emergency conditions, such as colds and headaches.

Understandably, the authors worry that reduced ER visits will lead to worsening health outcomes -- and only time will tell if this is the case.  But in the meantime, this study reminds us of a very important thing (with apologies to the late Milton Friedman): nobody spends someone else's money as carefully as he spends his own.