Adjusted association between the lymph node ratio and survival of patients with N1 lung cancer
| Variable | Lung cancer-specific survival HR (95% CI*) | Overall survival HR (95% CI) |
| Lymph node ratio | ||
| ≤0.15 | Reference | Reference |
| 0.16–0.5 | 1.26 (1.07 to 1.48) | 1.31 (1.14 to 1.50) |
| >0.5 | 1.92 (1.57 to 2.34) | 1.88 (1.58 to 2.34) |
| Age, years | 1.02 (1.01 to 1.03) | 1.02 (1.01 to 1.03) |
| Female | 0.82 (0.71 to 0.95) | 0.80 (0.70 to 0.91) |
| Race/ethnicity | ||
| White | Reference | Reference |
| Black | 0.69 (0.48 to 1.03) | 0.79 (0.58 to 1.08) |
| Hispanic | 0.41 (0.16 to 0.96) | 0.59 (0.31 to 1.10) |
| Other | 1.03 (0.78 to 1.37) | 1.08 (0.85 to 1.37) |
| Married | 0.90 (0.78 to 1.05) | 0.85 (0.75 to 0.97) |
| Median income in ZIP code of residence | ||
| Lowest quartile | Reference | Reference |
| Second quartile | 0.97 (0.80 to 1.17) | 1.02 (0.87 to 1.21) |
| Third quartile | 0.84 (0.70 to 1.03) | 0.86 (0.73 to 1.02) |
| Highest quartile | 0.83 (0.69 to 1.02) | 0.90 (0.76 to 1.06) |
| Comorbidity score, N (%) | ||
| ≤1 | Reference | Reference |
| 1–2 | 1.05 (0.90 to 1.25) | 1.08 (0.94 to 1.23) |
| >2 | 1.32 (1.11 to 1.56) | 1.42 (1.23 to 1.65) |
| Histology | ||
| Adenocarcinoma | Reference | Reference |
| Bronchioloalveolar carcinoma | 0.97 (0.74 to 1.26) | 0.91 (0.71 to 1.15) |
| Squamous cell carcinoma | 0.79 (0.67 to 0.93) | 0.82 (0.71 to 0.94) |
| Large cell | 1.02 (0.78 to 1.34) | 1.03 (0.81 to 1.30) |
| Other | 1.12 (0.82 to 1.56) | 1.05 (0.79 to 1.40) |
| Tumour status | ||
| T1A | Reference | Reference |
| T1B | 1.13 (0.85 to 1.50) | 1.08 (0.86 to 1.37) |
| T2A | 1.55 (1.21 to 1.99) | 1.36 (1.10 to 1.66) |
| T2B | 1.89 (1.40 to 2.55) | 1.60 (1.25 to 2.06) |
| T3 | 2.05 (1.54 to 2.74) | 1.77 (1.40 to 2.25) |
| Tumour location | ||
| Upper lobe | Reference | Reference |
| Lower lobe | 1.16 (1.01 to 1.33) | 1.08 (0.97 to 1.24) |
| Other location | 1.13 (0.88 to 1.46) | 1.19 (0.96 to 1.47) |
| Type of surgery | ||
| Lobectomy | Reference | Reference |
| Pneumonectomy | 1.26 (1.04 to 1.54) | 1.23 (1.03 to 1.45) |
| Postoperative radiation therapy | 1.19 (1.03 to 1.37) | 1.24 (1.10 to 1.40) |
| Adjuvant chemotherapy | 0.76 (0.63 to 0.91) | 0.69 (0.55 to 0.75) |
↵* Adjusted HRs from model including all covariates listed in the table.