Data breach at health care organization may affect 2 million people, including in Maine. Massachusetts-based Shields Health Care Group Inc. provides imaging and ambulatory surgical services at dozens of locations. BOSTON — A digital attack on a Massachusetts-based health care organization may have compromised the personal information of as many as 2 million people, officials said. Shields Health Care Group Inc., which provides imaging and ambulatory surgical services at dozens of locations, said in a notice on its website Tuesday that data including names, Social Security numbers, dates of birth, and medical or treatment details is among the information that may have been compromised. Third-party company: Shields Health Care Group Inc..