Efforts by employer groups to establish caps on medical procedures and identify quality providers may get a boost from data derived from Medicare and other data bases by a patient advocacy group. The data reveal vast differences in billings for similar procedures, and uncovered major overbilling trends — exactly the kinds of situations employers are attempting to control.

The advocacy group NerdWallet released its findings based upon three areas of research: analyzing federal data from the Centers for Medicaid and Medicare; consulting the Association of Credit and Collections Professionals; and commissioning a Harris Poll that gathered input from 2,000 consumers on health care spending.

The latest report represents a follow up of sorts of a study launched by NerdWallet last year, when it released findings that "nearly 60 percent of all personal bankruptcies in the United States are caused by medical debt."