Operative cost data was gathered from the Brigham and Women ‟ s Hospital billing system and the remainder of data was extracted from the patients ‟ medical records.
Upplýsingar um aðgerðakostnað fengust úr reikningsbókhaldi Brigham and Women ‟ s sjúkrahússins en aðrar upplýsingar fengust úr sjúkraskrám.