Prothrombin Time and Activated Partial Thromboplastin Time Testing: A Comparative Effectiveness Study in a Million-Patient Sample. oleh Manu N Capoor, Jerry L Stonemetz, John C Baird, Fahad S Ahmed, Ahsan Awan, Christof Birkenmaier, Mario A Inchiosa, Steven K Magid, Kathryn McGoldrick, Ernesto Molmenti, Sajjad Naqvi, Stephen D Parker, S M Pothula, Aryeh Shander, R Grant Steen, Michael K Urban, Judith Wall, Vincent A Fischetti