Table 1.
Characteristics of the two independent breast cancer patient cohorts in this study: those retrospectively observed before the initiation of a feedback and tracking registry (1999–2000) and those tracked after its implementation (2004–2006)
| Characteristic | Preintervention patients (n = 639) | Postintervention patients (n = 300) | P value* |
| Age, no. (%) | .03 | ||
| <70 y | 465 (73) | 238 (79) | |
| ≥70 y | 174 (27) | 62 (21) | |
| Insurance type, no. (%) | .04 | ||
| Commercial | 297 (46) | 164 (55) | |
| Medicaid | 121 (19) | 57 (19) | |
| Medicare | 179 (28) | 69 (23) | |
| No insurance | 42 (7) | 10 (3) | |
| Race†, no. (%) | <.001 | ||
| White | 307 (48) | 172 (57) | |
| Black | 136 (21) | 56 (19) | |
| Hispanic | 103 (16) | 56 (19) | |
| Asian | 28 (4) | 11 (4) | |
| Unknown | 65 (10) | 5 (2) | |
| Comorbidity ≥1, no. (%) | 130 (20) | 82 (27) | .02 |
| Breast cancer stage, no. (%) | .04 | ||
| IA | 92 (14) | 55 (18) | |
| IB | 255 (40) | 116 (39) | |
| IIA | 213 (33) | 79 (26) | |
| IIB | 79 (12) | 50 (17) | |
| Surgery type, no. (%) | .05 | ||
| Mastectomy | 243 (38) | 94 (31) | |
| Breast-conserving surgery | 396 (62) | 206 (69) | |
| Used tertiary referral center, no. (%) | 483 (76) | 224 (75) | .76 |
| Cases per surgeon, median (range) | 6 (1–78) | 6 (1–47) | .94 |
*
Categorical variables were tested with the chi-square test, continuous variables with the t test, and medians with the Wilcoxon test.
†
There were no statistically significant differences between the ratio of black and Hispanic vs white and Asian women in the pre- vs postintervention patient populations (P = .67).