Public agencies also develop practice guidelines. U.S. federal and state agencies and public agencies from other countries accounted for more than 500 of the guidelines in the National Guideline Clearinghouse.

Some groups involved in guideline development have sought partners. For example, the American College of Cardiology and the American Heart Association have collaborated in their guideline development program since the 1980s (ACC/AHA, 2009). Several groups are investigating an international collaboration to develop guidelines for the care of respiratory diseases (personal communication, Holger Schunemann, M.D., Ph.D., chair, Department of Clinical Epidemiology and Biostatistics, McMaster University, February 19, 2009). Compared with the complexity of simply adding individuals with different professional and other backgrounds to a guideline development panel, the management of partnerships between and among agencies tends to be more complicated because each partner usually has, for example, its own policies and procedures. Nevertheless, the