JUDY WOODRUFF:

Now: the rising use of outpatient medical centers for surgeries and other procedures.

It's a corner of the American health care market that rarely gets public attention. But after the death of comedian Joan Rivers, who suffered from complications at one facility in Manhattan, there are larger questions being asked about those centers, as their numbers are growing. There are more than 5,000 of them performing a total of 23 million surgeries a year.

Hari Sreenivasan fills in the picture from our New York studios.