Table 5.

Variables significantly related to duration of local tumor control in a final parsimonious Cox multivariable proportional hazards regression model following backward elimination. The hazard ratio, its 95% confidence interval (CI) for group comparison or a meaningful increment in a continuous predictor, and p-value for testing hazard ratio=1 are reported.

Predictor	Unit Change	Hazard Ratio	95% CI	P-value
Thermal Dose Group	Low vs. High	2.28	1.12–4.64	0.023
Total Duration of Heating (min; continuous)	30	1.09	1.02–1.17	0.008
Tumor volume (cm3; continuous)	30	1.09	1.00–1.19	0.041
Tumor Grade	High vs. Low/Intermediate	2.19	1.09–4.37	0.027