In North Carolina, Duke’s health system has been aggressively buying up local cardiology practices, thereby increasing the number of echocardiograms performed “in the hospital” by 68 percent in one year, and bumping the Medicare payment from $200 to $471, according to The Charlotte Observer and The News & Observer, in Raleigh.

It’s happening in my hometown hospital, Boulder Community Hospital, where my late mother was a trustee. The Denver Post reported in May on a patient whose cardiac stress test cost around $2,000 one year, and around $8,000 the next, after his doctor’s practice was bought by the hospital.

Same office, same machine, same doctor, but it cost four times more. Mom would want to know: what happened to the word “community” next to the word “hospital”?

The problem is not just prices, but also volumes: how much we do to patients, and how often. Look at colonoscopies. There are good reasons to believe that they can reduce the number of deaths from colon cancer. Expert panels recommend that most people need a colonoscopy only once every 10 years. But a study published in 2011 in The Archives of Internal Medicine found that 46 percent of Medicare beneficiaries with a normal colonoscopy nevertheless had a repeat exam in fewer than seven years. For some gastroenterologists, it seems, the primary finding from your colonoscopy is that you need another one.

Cardiology has a similar problem. Each year millions of Medicare beneficiaries undergo an echocardiogram. Half of them have the test repeated within three years. It sure looks as if some cardiologists are doing the test annually.

Finally we’ve learned the value of new capacity: if you build it, they will come. Two proton beam facilities were recently approved for Washington. One is already being built in Baltimore, only 40 miles away. There may be some role for proton beam radiation in children who have brain and spinal tumors, but there are only about 140 such children a year in Washington and Baltimore. Three facilities have the capacity to serve well over 10 times that. It’s hard to imagine that some of the roughly 8,000 men in the area destined to develop prostate cancer next year won’t receive proton beam therapy, despite the fact that there’s no good evidence that it’s any better than standard radiation for their condition.