The use of intraservice work per unit of time (IWPUT) and the building block method (BBM) for the calculation of surgical work.
Mabry CD, McCann BC, Harris JA, Martin J, Gage JO, Fischer JE, Opelka FG, Zwolak R, Borman K, Preskitt JT, Collicott PE, McGinnis L, Cohn I. The use of intraservice work per unit of time (IWPUT) and the building block method (BBM) for the calculation of surgical work. Ann Surg. 2005 Jun; 241(6):929-38; discussion 938-40.