Associations of General Practitioner Supplies with Breast Cancer 5-Year Survival among Women in Ontario Diagnosed Between 1995 and 1997 and Followed Until January 1, 2003
| General Practitioner Supply Predictor | Risk Factor | Prevalence (%) | Breast Cancer5-Year Survival(odds ratio [95% CI]) |
|---|---|---|---|
| Provincial analysis of 17,829 breast cancer cases | |||
| ≥7 per 10,000 in 2001 | <7 | 66.2 | 1.09 (0.98, 1.21)* |
| ≥7.25 per 10,000 in 2001 | <7.25 | 68.1 | 1.14 (1.01, 1.29) |
| Analysis of 10,745 cases outside the greater metropolitan Toronto area | |||
| Decreased by ≥3 per 10,000 in 1991 and 2001† | 16.5‡ | 0.83 (0.68, 1.03)§ |
All effects were adjusted for patient age, census tract low-income prevalence, census division age distribution, distance from regional cancer centers, and obstetrician/gynecologist supplies. Total physician density did not enter the model. There were 10,291 and 10,122 active general practitioners in Ontario in 1991 and 2001, respectively.
* 90% confidence interval did not include the null (1.00–1.19; P < .10).
† Sensitivity analyses revealed the most predictive criterion decrement.
‡ Overrepresented by small to mid-sized cities with populations between 100,000 and 500,000.
§ 90% CI did not include the null (0.70–0.99; P < .10).