A group of us have gotten into a discussion about health care manpower training in Alabama. This started as we were trying to determine if a certain Internal Medicine program was putting out primary care doctors (only 8% of their graduates are currently doing traditional primary care) and the statement was made “If you count hospitalists, they put out 44% primary care.” A hospitalist has been through the same training as other doctors who provide primary care, but in practice doesn’t spend their time interacting with people in the office to keep them out of the hospital. Instead these doctors work with sick people in the hospital to treat them efficiently and get them out quickly. They care for patients for a very intense 36 hours then send them on their way, hopefully never to see them again. They do help make the primary care system work more efficiently.  In the words of one colleague:
They free [up] primary care physicians  to spend more time in clinic and in the management of their patients’ care. They also can lower the stress level, improve the lifestyle, and sometimes even increase the income of those primary care physicians.
Why is this important? Medical students must have residency training following medical school in order to practice. There are currently not enough residency training slots for all of the graduates of medical schools. There will likely be more training programs established and given the emphasis on primary care the ability of programs to train primary care docs will likely lead to more money. Family Medicine programs tend to put over 90% of their graduates into primary care. Internal Medicine and Pediatric programs, not so much.
I looked up the Medicare definition of primary care to be helpful in this discussion since they pay the bills (I will add Cliff Notes in italics for the non-professional)

Policy: The ACA defines a primary care practitioner as: (1) a physician who has a primary specialty designation of family medicine, internal medicine, geriatric medicine, or pediatric medicine; (note that this does not include OB/GYNs, surgeons, cardiologists, or many types of doctors)  or (2) a nurse practitioner, clinical nurse specialist, or physician assistant, and in all cases, for whom primary care services (as defined below) accounted for at least 60 percent of the allowed charges under Part B (the part of Medicare that pays for doctor visits) for the practitioner in a prior period as determined appropriate by the Secretary.
The ACA defines primary care services as those identified by the following CPT (the number we put on bills to tell the insurance company what we did) codes:
• 99201 through 99215 for new and established patient office or other outpatient evaluation and management (E/M) visits (folks seen in the office);
• 99304 through 99340 for initial, subsequent, discharge, and other nursing facility E/M services; new and established patient domiciliary, rest home (e.g., boarding home), or custodial care E/M services; and domiciliary, rest home (e.g., assisted living facility), or home care plan oversight services; (folks seen in non-office but settings where people live) and
• 99341 through 99350 for new and established patient home E/M visits (patients seen at home).

 So that would be a NO to hospitalists as primary care docs.