Statistical package for social sciences spss for windows version 17

The relation of age (younger vs older) with clinicopathological features was analyzed by chi-square (χ2) test. Comparisons of continuous variables between two groups were completed using Student’s t-test. Survival was analyzed based on age (younger vs older) and was stratified by AJCC stages I–IV, or unknown stage. Survival curves were provided by Kaplan–Meier estimates; differences between two groups were analyzed by log-rank test. Multivariate Cox regression models were performed to evaluate risk factors for survival outcomes. All statistical analyses were completed using the statistical software Statistical Package for Social Sciences (SPSS) for Windows, version 17 (SPSS Inc., Chicago, IL, USA). P < 0.05 was considered significant.

The results of the CBMN assay are expressed as the mean frequency ± standard error (MF ± se). The statistical analysis of the MN data was accomplished using the G-test for independence on 2 × 2 tables, whereas the chi-square test (χ² test) was used for the analysis of CBPI among each treatment. Differences at p < 0.05 were considered significant. The Origin 7.0 (Origin Lab Corporation, Northampton, MA, USA), the Minitab statistical software (Minitab Inc., PA, USA) and the Statistical Package for Social Sciences (SPSS) for Windows, version 17 were the statistical software used for data analysis.
SMART assay genotoxicity results were analyzed using the multiple-decision procedure, which is based on the conditional binomial test and the chi-squared test (K. Pearson’s criterion), as previously described^{4 (link),5 (link)}. Antigenotoxicity results were analyzed using the nonparametric Mann-Whitney U-test to compare the spot frequencies in pairs (negative control versus compounds; MMC versus MMC + compounds)^{4 (link),5 (link)}. The used significance level was 5%.