Table 5. Comparison of the prognostic performances of the 7th AJCC and novel subclassifications.

Variable	Staging system	Linear trendchi-square*	Likelihood ratiochi-square†	AIC¶	Figure
Stage	AJCC stage	166.1493	182.3456	6252.888	3A
	Novel stage	177.3985	198.6962	6236.538	3B
pT4 subclassification	AJCC pT4	53.3501	53.9337	6381.300	2A
	Novel pT4	103.6116	108.6238	6326.610	2B

AIC, Akaike information criterion.

^*Higher linear trend chi-square scores show better discriminatory ability and gradient monotonicity.

^†A higher likelihood ratio chi-square score means better homogeneity.

^¶Smaller AIC values indicate better optimistic prognostic stratification.