The cost allocation system used by the hospital incorporates the cost of the residents. We found that cost of care was similar on teaching and nonteaching services in our institution (1). Hospitalists have been involved in teaching residents both in the present hospital managed program and in the original program. The hospitalist program was not disbanded. Management was transferred from the Department of Medicine teaching faculty to hospital administration to expand the program and to separate administration of the hospitalist program from administration of the medical residency. The faculty member who had the largest hospitalist role now has a senior leadership position in the hospital program. Support of the hospitalists has always been shared between the covered practices and the hospital. Support from each source has not changed. The original physician group participating in the hospitalist program is now in its fourth year of participation. Length of stay has continued to decrease (4.9 days).

The second comparison group represented physician groups with the longest length of stay in the prehospitalist year. This subset was chosen as a check for the concern that length of stay might be reduced more in a group with a longer-than-community-average length of stay. We agree with Dr. Bellin that a hospitalist program has both gains and losses. Resources were not diverted to the hospitalist program. However, the presence of the hospitalists in the hospital and their familiarity with available resources and personnel could give them a disproportionate share of hospital resources, as suggested by Dr. Bellin. Length of stay has decreased in both groups this year. More than 90% of readmissions were for diagnoses different from the prior admission.

Additional studies must be done to answer Dr. Bellin's questions. Given the rapid growth of the hospitalist movement, we believe that these studies are needed.