Three of the nation's largest health insurance companies have agreed to participate in a database that will provide consumers with free price and quality data on health care services. The Health Care Cost Institute, a Washington, D.C.-based nonprofit launched in 2011 to promote independent, nonpartisan research and analysis on the causes of the rise in U.S. health spending, announced today that Aetna Inc., Humana Inc. and United Healthcare Services Inc. will provide data for an online portal that will be managed by the institute. The new transparency tool, which HCCI expects to make available by early next year, will aggregate pricing data from commercial health plans as well as Medicare Advantage and Medicaid health plans, if the states agree to provide it. The organization said other major insurance carriers have expressed interest and may be part of the initial release in early 2015.