title: Physician assistants in American medicine: the half-century mark.
abstract: BACKGROUND
  The concept of the physician assistant (PA) was developed by US physicians in the 1960s as a workforce strategy to improve the delivery of medical services. Then as now there is an anticipated shortage of physicians, particularly in primary care. Use of PAs is viewed as 1 possible strategy to mitigate this growing gap in provider services.
  
  
  OBJECTIVE
  To describe the PA in US medicine for policy background and analysis.
  
  
  METHODS
  In January 2013, approximately 89,500 PAs were licensed: 65% were women. Four-fifths were under the age of 55 years. PAs are trained in 2.5 years at one-fourth the cost of a physician and begin producing patient care 4 years before a physician is independently functional. One-third of PAs work with primary care physicians; 65% work in non-primary care practices. Popular specialties are family medicine, emergency medicine, surgery, and orthopedics. PAs are revenue producers for employers and expand access and clinical productivity in most practice settings. Roles for PAs have expanded into hospital settings and graduate medical education programs. About 7300 PAs graduate annually, and this number is expected to grow to 9000 by the end of the decade. Predictive modeling suggests that demand for medical services will grow faster than the combined supply of physicians, PAs, and nurse practitioners, particularly in primary care. PA quality of care appears indistinguishable from that of physician-delivered services.
  
  
  CONCLUSIONS
  Optimal organizational efficiency and cost savings in health services delivery will depend on how well the PA can be utilized.
authors.affiliation: Professor, Department of Prevention and Community Health, The George Washington University, 2175 K Street, NW, Washington, DC 20037. E-mail: purljfc@aol.com.
authors.forename: James F
authors.initials: JF
authors.lastname: Cawley
authors.forename: Roderick S
authors.initials: RS
authors.lastname: Hooker
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007400:Interprofessional Relations; D008297:Male; D008875:Middle Aged; D010823:Physician Assistants / Q000193:education / Q000331:legislation & jurisprudence / Q000600:supply & distribution; D011320:Primary Health Care; D011787:Quality of Health Care; D012424:Rural Population; D014481:United States; D000078329:Workforce; D055815:Young Adult