The lede:

Twenty-one states have mandated hospital infection reporting in the last four years, and 221 health care quality report cards are listed on a Health and Human Services Web site.

Last month alone saw new quality reports released in New Jersey, Minnesota and the Seattle area.

The premise behind this wave of public reporting is that transparency will spur doctors and hospitals to improve quality and safety while giving patients valuable data to help them decide where to seek care. The concept has widespread
acceptance, yet it is also largely untested and unproven.

Since 1986, 45 studies have examined the impact of public reports on quality and safety. But while such reports appear to stimulate quality activity in hospitals, there is little evidence to show they improve the effectiveness, safety or patient-centeredness of care. They also can have unintended consequences, such as discouraging doctors from treating sicker patients.

The whole shebang.