Boston Children's Hospital formerly known as Children's Hospital Boston until 2012 is a nationally ranked, freestanding acute care children's hospital located in Boston, Massachusetts, adjacent both to its teaching affiliate, Harvard Medical School, and to Dana-Farber Cancer Institute. Dana-Farber and Children's jointly operate the Dana-Farber/Boston Children's Cancer and Blood Disorders Center to deliver comprehensive care for all types of childhood cancers. The hospital is home to the largest hospital based pediatric research program in the world. The hospital features 404 pediatric beds and provides comprehensive pediatric specialties and subspecialties to infants, children, teens, and young adults aged 0–21 throughout Massachusetts, the United States, and the world. The hospital also sometimes treats adults that require pediatric care. The hospital uses the Brigham and Women's Hospital's rooftop helipad and is an ACS verified level I pediatric trauma center, 1 of 3 in Boston. The hospital features a regional pediatric intensive-care unit and an American Academy of Pediatrics verified level IV neonatal intensive care unit. Children's Hospital Boston has been ranked as best pediatric medical center by "U.S. News & World Report" more times than any other hospital.