Table 4.

Estimated regression parameters for the two-stage regression model

	Coefficients	Std err	t-statistic	Probability	95% LCI	95% UCI
Pemetrexed R2 = 28.2%
b1	442	65	6.76	<0.001	312	571
b0	6835	602	11.35	<0.001	5643	8028
Erlotinib R2 = 35.3%
b1	489	58	8.45	<0.001	375	604
b0	5275	592	8.92	<0.001	4104	6445

Note: b₁ expresses the “time” estimator and is measured in months.

Abbreviations: LCI, lower confidence Interval; UCI, upper confidence interval; Std err, standard error.