Health care reform continues to be a key political topic of discussion in the U.S. Physician supply and specialty training are important elements in designing an efficient system that provides the highest quality of care.

To understand where U.S. physician supply and specialty training is headed, I examined the U.S. trends from 1990 to 2007 (latest year data is available).

Physician supply has been growing during this period. In 1990, there were 615,000 physicians in the U.S. and by 2007 this figure had increased by 53% to 941,000. This came during a period when the total U.S. population increased approximately 25%

Which specialties are growing at rates higher than the total overall physician growth rate? Surprisingly, the primary care specialties all grew at a rate above 53%. The top five specialties in growth rate included: emergency medicine 116%, physical medicine and rehabilitation 101%, pediatrics 85%, family practice 77% and pulmunology 72%. In addition, the number of physicians in internal medicine grew by 61% over this period.

The high growth rate in emergency medicine physicians probably reflects growth in emergency medicine residency-trained doctors replacing and supplementing other specialty physicians who work in the emergency room.

Which specialties grew at a rate slower than average? The bottom five specialties for growth from 1990 to 2007 were: general surgery -2%, urology 12%, ophthalmology 13%, psychiatry 18% and pathology 19%. A shortage of general surgery doctors is generally recognized and recent plateaus in the supply in this specialty contributes to this problem. Lagging growth rates in psychiatric physicians may pose challenges to implemented extended mental health coverage planned for the U.S.

Female physician numbers grew at a rate of 156% over this period. Female physicians now account for 28% of all physicians in the U.S. compared to 17% in 1990. Female physicians have different specialty selection preferences and working patterns than men. These differences will affect how the physician workforce evolves in the next ten to twenty years.

Primary care physician specialty designation (internal medicine, pediatrics and family medicine combined) now makes up 34% of all physicians, up from 30% in 1990. Addressing the primary care shortage will require support for residency training in these specialties and reduction in payment gaps.

In summary, the recent trend in physician supply in the U.S. shows significant growth over the general population rate. Primary care physician numbers are also growing faster than other specialties. Planning for future physician supply will need to understand this trend and recognize the growing portion of female physicians.

William Yates is a family physician who blogs at Brain Posts.

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