Primary care health workforce in the United States.

As a result of the Patient Protection and Affordable Care Act, more than 30 million people are expected to be newly insured, many of whom will be seeking a source for primary care. At the same time, media reports and some studies are proclaiming a current or imminent shortage of primary care providers. This Synthesis examines the evidence on the primary care workforce including: the supply and distribution of the workforce; the historical and projected demand on the primary care workforce; the effects of payment policies and scope of practice laws on the workforce; and how the primary care workforce is evolving.