Table 2.

Multicovariate analysis of time to oral cancer on quantitative EGFR expression (E/N = 29/127)^*

Variable	Hazard Ratio	95%	CI for HR	P-value
Age	1.05	1.01	1.08	0.005
13cRA vs. BC-RP/RP only	0.83	0.39	1.76	0.626
Histologic status at baseline: dysplasia versus hyperplasia	2.99	1.42	6.29	0.004
EGFR transformed total composite score	1.15	1.01	1.30	0.036

Abbreviations: EGFR, epidermal growth factor receptor; E, number of events; N, number of patients; Pr > ChiSq, P-value; HR, hazard ratio; CI, confidence interval; BC, β-carotene; RP: retinyl palmitate; 13cRA, 13-cis-retinoic acid; FISH, fluorescence in situ hybridization.

^*For this analysis, the Cox proportional models were fitted with other important factors in the models. Composite scores of membrane staining and cytoplasmic staining were obtained by multiplying the number of positive cells by the intensity. The sum of the membrane and cytoplasmic scores was used to generate a total composite EGFR score, which then was transformed by dividing its square root by 10,000. This analysis produced the maximum-likelihood estimates.