A national organization of health care executives has agreed to disband amid an investigation by Connecticut authorities into whether it illegally gave preferential treatment to vendors who joined the group.

Connecticut State Attorney General Richard Blumenthal announced an antitrust settlement Thursday with Healthcare Research and Development Institute, based in Pensacola, Fla. Under the deal reached with the offices of Blumenthal and Florida Attorney General Bill McCollum, HRDI also agreed to pay Connecticut $150,000.