Statistical learning methods as a preprocessing step for survival analysis: evaluation of concept using lung cancer data

Table 5 Survival probability statistical test summaries

Model	Test	Chi-Square	DF	p-value
Accepted
Dichotomous Age over Strata	Log-Rank	4.1784	1	0.0409
	Wilcoxon	3.4073	1	0.0649
Dichotomous Age and Gender over Strata	Log-Rank	12.7383	3	0.0052*
	Wilcoxon	13.5117	3	0.0043*
Hybrid
Dichotomous z over Strata	Log-Rank	22.7597	1	< 0.0001
	Wilcoxon	14.9418	1	0.0001
Dichotomous z and Gender over Strata	Log-Rank	28.1863	3	< 0.0001*
	Wilcoxon	22.4886	3	< 0.0001*

The statistical tests findings for the various age an z related survival probability curves are provided with the degrees of freedom (DF). When comparing more than two survival curves (*), the hypothesis that all the curves were the same was tested against the alternative that at least one curve was different.

ISSN: 1475-925X