title: Measuring primary care: the standard primary care year.
abstract: BACKGROUND
  Numerous reports highlight the problem of declining primary care capacity in the USA, especially in rural and remote areas. The reasons for declining primary care capacity are elusive. Little progress is likely without better definitions, tools, and approaches. The author proposes a standard primary care workforce year to adjust each primary care form for losses due to specialization, lower levels of practice activity, lower primary care volume, and shorter career length.
  
  
  METHODS
  The author reviewed studies to create a standard primary care year estimate representing the total primary care contribution for each of the five training forms of primary care over the career length of the graduate. The standard primary care year was the product of four factors: (1) the career length in years; (2) the percentage estimated to remain in primary care; (3) the percentage active in practice; and (4) the percentage of primary care volume compared with a family practitioner. A best determination was made regarding the value of each of the four factors for each primary care form. Because specialization rates increased substantially to decrease primary care contributions, the estimate for each form also had to be linked to each class year of graduates.
  
  
  RESULTS
  Family practice is the best example of a permanent primary care training form with 29.3 standard primary care years expected over a 35 year career. Other training forms appear to be more flexible with graduates able to choose primary care or specialty care depending on policy and market forces. The 2008 pediatric residency graduates can be expected to serve 17.6 years of primary care. Internal medicine resident primary care contributions have been reduced by 50% in the past decade to 5.3 years with international medical graduate internal medicine contributions decreasing to 2.5 years. Physician assistant estimates have decreased to 6 years, while nurse practitioner estimates have declined below 3 years per graduate. Without changes in policy or training, the USA must graduate 11.7 international medical graduate internal medicine residents, or 10 nurse practitioners, or 5.5 US internal medicine residents, or 4.8 physician assistants, or 1.7 pediatric residents to equal the same primary care contributions as one family physician. With decreasing rural and underserved distribution levels in the flexible forms, the numbers of graduates needed to match the family practice rural primary care year and underserved primary care year contributions are even higher.
  
  
  CONCLUSIONS
  The primary care year is a versatile tool that can help to estimate primary care contributions across different forms of primary care. Specialization takes a huge toll on primary care capacity. Progressive failure to retain primary care makes expansions of graduates an ineffective and costly intervention. Without graduating more who remain in primary care, the USA can expect consistently lower primary care levels. Primary care contributions of progressively shorter duration could explain the perceived rapid collapse of primary care, particularly when studies of primary care fail to involve the most recent months of changes.
authors.affiliation: AT Still University School of Osteopathic Medicine in Arizona, Mesa, Arizona, USA. rcbowman@atsu.edu
authors.forename: R C
authors.initials: RC
authors.lastname: Bowman
mesh_terms: D006801:Humans; D008507:Medically Underserved Area; D008511:Medicine; D010821:Physicians, Family / Q000600:supply & distribution*; D011320:Primary Health Care; D011365:Professional Practice Location; D011785:Quality Assurance, Health Care / Q000379:methods; D019035:Rural Health Services; D013038:Specialization; D014481:United States; D000078329:Workforce