Table 2.
Descriptive statistics by annual surgeon volume based on a cohort of California women who underwent ovarian cancer resection from 1991–2002
| Variable | High-volume surgeon (HVS) (N=3249) |
Middle-volume surgeon (MVS) (N=4104) |
Low-volume surgeon (LVS) (N=5833) |
P value |
|---|---|---|---|---|
| Patient demographics | ||||
| Age (years) | ||||
| Mean±standard deviation | 58.4±14.7 | 59.0±14.6 | 56.6±16.3 | <0.001a |
| Race/ethnicity (%) | <0.001 | |||
| Non-Hispanic White | 77.5 | 71.5 | 69.7 | |
| Black | 2.8 | 4.1 | 4.0 | |
| Hispanic | 12.5 | 16.4 | 18.1 | |
| Asian | 6.9 | 7.6 | 7.8 | |
| Other | 0.3 | 0.4 | 0.4 | <0.001 |
| Payer (%) | ||||
| Private | 60.6 | 54.3 | 51.5 | |
| Medicare | 20.4 | 22.8 | 21.0 | |
| Medicaid | 4.7 | 6.6 | 5.6 | |
| Uninsured | 2.5 | 2.0 | 2.1 | |
| Other | 11.8 | 14.3 | 19.8 | |
| % <200% poverty level | ||||
| Mean±standard deviation | 28.8±17.7 | 29.3±18.2 | 28.8±18.1 | 0.500 a |
| Medical comorbid disease | ||||
| Revised Charlson | <0.001 | |||
| Comorbidity Index (%) | ||||
| Charlson 0 | 80.3 | 78.4 | 81.9 | |
| Charlson 1 | 14.4 | 15.1 | 12.5 | |
| Charlson 2+ | 5.3 | 6.5 | 5.6 | |
| Ovarian cancer characteristics | ||||
| Ovarian cancer stage (%) | <0.001 | |||
| Stage I | 28.7 | 31.7 | 47.7 | |
| Stage II | 8.9 | 8.1 | 9.1 | |
| Stage III | 48.2 | 46.5 | 31.5 | |
| Stage IV | 14.2 | 13.7 | 11.7 | |
| Tumor differentiation (%) | <0.001 | |||
| Well differentiated | 8.7 | 8.0 | 9.5 | |
| Moderately differentiated | 19.5 | 17.5 | 17.0 | |
| Poorly differentiated | 35.8 | 38.0 | 28.3 | |
| Undifferentiated | 9.9 | 8.0 | 5.9 | |
| Other differentiation | 26.1 | 28.5 | 39.3 |
a
Comparison of continuous variable means between women undergoing ovarian cancer resection by a HVS and LVS.