Table 4.
The Effect of a Hypothetical Unmeasured Binary Confounder on the Adjuvant Chemotherapy Hazard Ratio
| UBC Prevalence, % | UBC HR for Overall Survival | Adjuvant Chemotherapy, HR (95% CI) Adjusted for UBCa | |
|---|---|---|---|
| CRT Group | RT Group | ||
| 50 | 0 | 4.00 | 0.58 (0.36–0.93) |
| 90 | 10 | 4.00 | 0.51 (0.32–0.82) |
| 50 | 0 | 3.00 | 0.73 (0.46–1.17) |
| 70 | 0 | 3.00 | 0.61 (0.38–0.97) |
| 90 | 10 | 3.00 | 0.63 (0.39–1.00) |
| 100 | 0 | 2.00 | 0.73 (0.46–1.17) |
| CRT Group | RT Group | UBC HR for Disease-Free Survival | Adjuvant Chemotherapy, HR (95% CI) Adjusted for UBCb |
| 20 | 0 | 3.00 | 0.65 (0.42–1.01) |
| 30 | 0 | 3.00 | 0.57 (0.37–0.89) |
| 30 | 10 | 3.00 | 0.68 (0.44–1.06) |
| 40 | 10 | 3.00 | 0.61 (0.39–0.95) |
| 40 | 0 | 2.00 | 0.65 (0.42–1.01) |
| 50 | 0 | 2.00 | 0.61 (0.39–0.95) |
| 50 | 10 | 2.00 | 0.67 (0.43–1.04) |
| 60 | 10 | 2.00 | 0.63 (0.41–0.98) |
Abbreviations: aHR, adjusted hazard ratio; CRT, chemoradiotherapy; HR, hazard ratio; RT, radiotherapy; UBC, unmeasured binary confounder.
a
Inverse probability-weighted aHR for the relationship between adjuvant chemotherapy and overall survival (aHR, 95% CI, 1.46; 95% CI, 0.91–2.33) after further adjustment for unmeasured binary confounder.
b
Inverse probability-weighted aHR for the relationship between adjuvant chemotherapy and disease-free survival (aHR, 0.91; 95% CI, 0.59–1.42) after further adjustment for unmeasured binary confounder.