Table 3.
Regression Analysis Results*
| Variable | Radiation Therapy After Breast-Conserving Surgery |
Multiagent Chemotherapy for Breast Cancer |
Hormonal Therapy for Breast Cancer |
Adjuvant Chemotherapy for Colon Cancer |
12 Regional Lymph Nodes Excised During Colon Cancer Surgery |
||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| OR | 95% CI | P | OR | 95% CI | P | OR | 95% CI | P | OR | 95% CI | P | OR | 95% CI | P | |
| Intercept | 2.54 | 1.73 to 3.74 | < .001 | 3.14 | 1.99 to 4.96 | < .001 | 0.95 | 0.63 to 1.42 | NS | 3.33 | 1.74 to 6.38 | < .001 | 4.86 | 3.55 to 6.67 | < .001 |
| NCCCP in time 2 (v NCCCP in time 1)† | 2.94 | 2.05 to 4.20 | < .001 | 3.14 | 1.97 to 5.00 | < .001 | 5.00 | 3.73 to 6.70 | < .001 | 2.87 | 1.58 to 5.20 | < .001 | 2.03 | 1.53 to 2.69 | < .001 |
| NCCCP in time 1 (v comparison group in time 1)‡ | 0.91 | 0.52 to 1.58 | NS | 0.60 | 0.34 to 1.07 | NS | 0.68 | 0.41 to 1.01 | NS | 0.60 | 0.27 to 1.35 | NS | 1.22 | 0.83 to 1.79 | NS |
| NCCCP change in concordance between times 1 and 2 (v comparison group change)§ | 1.26 | 0.66 to 2.44 | NS | 1.53 | 0.80 to 2.92 | NS | 1.66 | 1.04 to 2.65 | < .05 | 1.71 | 0.83 to 3.51 | NS | 0.95 | 0.66 to 1.36 | NS |
Abbreviations: NCCCP, National Cancer Institute Community Cancer Centers Program; NS, not significant; OR, odds ratio.
*
As discussed in Methods section, regressions also controlled for race, age group, insurance status, and sex (regressions of colon cancer quality measures only).
†
Time variable (from regressions with NCCCP hospitals as reference group).
‡
NCCCP hospital group indicator variable.
§
Difference-in-difference term, examining difference in concordance rate over time between NCCCP and comparison hospitals.