Productivity versus availability as a measure of faculty clinical responsibility

Faculty clinical time is an extremely valuable commodity. Most departments quantify faculty clinical time on an "availability" basis (e.g., number of days in the operating room or nights on call). We hypothesize that a productivity measure (i.e., determination of actual clinical care delivered rather than availability of such care) would produce different results than the availability system. The "billable hour" was chosen as the measurement device. It was defined as time that anesthesia was actually given, as obtained from the anesthetic record. After collecting data for a year, we found that despite parity using the availability system, the billable hour system detected significant differences between faculty within and between groups. We conclude that "availability" and "productivity" systems produce different conclusions regarding the relative contributions of an individual faculty or subspecialty group.