PARTICIPANTS UNC PHYSICIANS NETWORK (UNC PEDIATRICS AT SOUTHPOINT ) REX PHYSICIAN SERVICES (REX PEDS CARY) UNC PHYSICIANS NETWORK (UNC PEDIATRICS AT WEAVER CROSSING) UNC PHYSICIANS NETWORK (UNC PEDIATRICS AT GARNER) UNCH CHILDRENS PRIMARY CARE FRANKLIN ST CHAPEL HILL UNC FAMILY MEDICINE AT SOUTHPOINT ORANGE FAMILY MEDICAL GROUP HILLSBOROUGH PITTSBORO FAMILY MEDICINE REX FAMILY MEDICINE OF WAKEFIELD UNC FAMILY MEDICINE AT HILLSBOROUGH CHATHAM PRIMARY CARE UNC PEDIATRICS PANTHER CREEK CARY THE FALLS PEDIATRIC ANDERSON MEDICAL PARK MULBERRY PEDIATRICS RIVER CREST MEDICAL PARK REX PRIMARY CARE OF HOLLY SPRINGS PARDEE FAMILY MEDICINE ASSOCIATES ETOWAH MEBANE PRIMARY CARE UNC FAMILY MEDICINE AT WEST RALEIGH NORTH CHATHAM PEDIATRICS AND INTERNAL MEDICINE CAPITOL PEDS AND ADOL CTR KNIGHTDALE CAPITOL PEDS AND ADOL CTR RALEIGH CAPITOL PEDS AND ADOL CTR WAKEFIELD WESTPOINTE MEDICAL PRACTICE UNC INT MED AND PEDS AT MIDDLESEX (MIDDLESEX POWELL) UNC FAMILY MEDICINE CAROMONT REGIONAL MEDICAL CENTER UNC HEALTH BLUE RIDGE VALDESE UNC HEALTH BLUE RIDGE MORGANTON SOUTHEASTERN REGIONAL MEDICAL CENTER