Associations of Obstetrics/Gynecology Specialist Supplies with Breast Cancer 5-Year Survival in Ontario: Women Diagnosed Between 1995 and 1997 Were Followed Until January 1, 2003
| Obstetrician/Gynecologist Supply Predictor | Risk Factor | Prevalence (%) | Breast Cancer5-Year Survival(OR [95% CI]) |
|---|---|---|---|
| Provincial analysis of 17,829 breast cancer cases | |||
| ≥6 per 100,000 in 2001 | <6 | 59.7 | 1.13 (1.01–1.27) |
| Analysis of 10,745 cases outside the greater metropolitan Toronto area | |||
| Decreased by ≥2 per 100,000 in 1991 and 2001* | 20.2† | 0.76 (0.61–0.96) |
All effects were adjusted for patient age, census tract low-income prevalence, census division age distribution, distance from regional cancer centers, and general practitioner supplies. Total physician density did not enter the model. There were 648 and 664 active obstetrician/gynecologists in Ontario in 1991 and 2001, respectively.
* Sensitivity analyses revealed the most predictive criterion decrement.
† Overrepresented by small to mid-sized cities with populations between 100,000 and 500,000.