title: Primary care physician supply and children's health care use, access, and outcomes: findings from Canada.
abstract: OBJECTIVE
  To describe the relationship of primary care physician (PCP) supply for children and measures of health care access, use, and outcomes.
  
  
  METHODS
  We conducted a population-based, cross-sectional study of all Ontario children from 2003 to 2005. We used health administrative data to calculate county-level supply (full-time equivalents [FTEs]) of PCPs. We modeled the relationship of supply to (1) recommended primary care visits, (2) emergency department (ED) use, and (3) ambulatory care-sensitive condition admissions and adjusted for neighborhood income. We used population-based surveys to describe access.
  
  
  RESULTS
  The county-level PCP supply ranged from 1720 to 4720 children per FTE. Of the children, 45.4% live in the highest-supply areas (<2000 children per FTE) and 8% in the lowest-supply areas (>3000 children per FTE). Compared with high-supply counties, the lowest had significantly lower rates of primary care visits (2716 vs 7490 per 1000) and higher proportions of newborns without early follow-care (58.2% vs 14.5%). Low-supply areas had higher rates of ED visits (440 vs 179 per 1000) and admissions. A stepwise gradient existed for every decrease in supply for most measures. Self-reported access barriers were most evident in areas with >3500 children per FTE (32.8% without a physician).
  
  
  CONCLUSIONS
  Under universal insurance there are differences in access to, and outcomes of, primary care related to local physician supply after controlling for neighborhood income. The most pronounced effect is on primary and ED care use, but there are implications for acute and chronic disease control. Physician distribution is a critical issue to address in policies to improve access to care.
authors.affiliation: Institute for Clinical Evaluative Sciences, 2075 Bayview Ave, G106, Toronto, Ontario, Canada M4N 3M5. astrid.guttmann@ices.on.ca
authors.forename: Astrid
authors.initials: A
authors.lastname: Guttmann
authors.forename: Scott A
authors.initials: SA
authors.lastname: Shipman
authors.forename: Kelvin
authors.initials: K
authors.lastname: Lam
authors.forename: David C
authors.initials: DC
authors.lastname: Goodman
authors.forename: Therese A
authors.initials: TA
authors.lastname: Stukel
mesh_terms: D002648:Child; D002662:Child Health Services / Q000706:statistics & numerical data*; D003430:Cross-Sectional Studies; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data; D006297:Health Services Accessibility / Q000706:statistics & numerical data*; D006302:Health Services Research; D006801:Humans; D016017:Odds Ratio; D009864:Ontario; D010043:Outcome and Process Assessment, Health Care; D010820:Physicians / Q000600:supply & distribution*; D011320:Primary Health Care; D000078329:Workforce