TABLE 4.
Results from the multivariate logistic regression model using generalized estimating equations. Patient and physician characteristics associated with nonhospital-based colonoscopy in Ontario in 2005 (n=251,985)
| Patient characteristics | OR (95% CI) | P |
|---|---|---|
| Age group, years | ||
| 19–50 | 1.4 (1.2–1.6) | <0.0001 |
| 51–70 | 1.5 (1.4–1.7) | <0.0001 |
| >70 | 1 | N/A |
| Sex | ||
| Male | 1.1 (1.0–1.2) | 0.01 |
| Female | 1 | N/A |
| Neighbourhood income quintile | ||
| Low | 0.6 (0.5–0.8) | <0.0001 |
| 2 | 0.6 (0.5–0.7) | <0.0001 |
| 3 | 0.6 (0.5–0.7) | <0.0001 |
| 4 | 0.7 (0.6–0.8) | <0.0001 |
| High | 1 | N/A |
| Comorbidity* | ||
| None | 2.0 (0.9–4.1) | NS |
| 1–3 | 1.4 (1.2–1.7) | <0.0001 |
| 4–5 | 1.2 (1.1–1.3) | <0.0001 |
| 6–7 | 1.2 (1.1–1.2) | <0.0001 |
| ≥8 | 1 | N/A |
| Physician characteristics | ||
| Specialty | ||
| General surgery | 3.8 (1.7–8.4) | 0.0009 |
| Internal medicine | 1.7 (0.5–5.7) | NS |
| Other practitioners | 6.1 (2.0–18.8) | 0.002 |
| Gastroenterology | 1 | N/A |
| Endoscopist volume quintile | ||
| Low | 0.04 (0.02–0.1) | <0.0001 |
| 2 | 0.03 (0.01–0.1) | <0.0001 |
| 3 | 0.05 (0.02–0.1) | <0.0001 |
| 4 | 0.3 (0.1–0.6) | 0.0025 |
| High | 1 | N/A |
*
Comorbidity scored using number of aggregated diagnosis groups. N/A Not applicable; NS Not significant