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ITP survival analysis:   nordihydroguaiaretic acid

Intervention:   nordihydroguaiaretic acid     antioxidant, anti-aging
Trial code: NDGA Dose: 2500 ppm initiated at age: 9 mo Sex: both Cohort: C2004
This compound had a significant effect on survival:   males p = 0.0006

Results are based on the use of pooled factor(s) that is/are stratified within the survival analysis model.

All test sites combined – female
NDGA effect on survival, females, test site = All
Log-rank test chisq = 0.1816 p = 0.67
Wang-Allison test odds ratio = 1.1018 p = 0.8634
Quantiles NDGA Control % difference
25% died before day: 764 739 +3 %
Median lifespan (days) 895 888 +1 %
75% died before day: 983 988 -1 %
90% died before day: 1094 1072 +2 %
Max lifespan observed (days) 1249 1212
Number of mice at start 139 271
Animal censor events are denoted by + marks in the plot
All test sites combined – male
NDGA effect on survival, males, test site = All
Log-rank test chisq = 11.8982 p = 0.0006
Wang-Allison test odds ratio = 1.5492 p = 0.1629
Quantiles NDGA Control % difference
25% died before day: 713 612 +17 %
Median lifespan (days) 881 784 +12 %
75% died before day: 989 912 +8 %
90% died before day: 1098 1048 +5 %
Max lifespan observed (days) 1267 1305
Number of mice at start 169 350
Animal censor events are denoted by + marks in the plot


By individual test site:

TJL – female
TJL – female      
NDGA effect on survival, females, test site = TJL
Log-rank test chisq = 0.008 p = 0.9287
Wang-Allison test odds ratio = 1.5498 p = 0.552
Quantiles NDGA Control % difference
25% died before day: 748 738 +1 %
Median lifespan (days) 892 858 +4 %
75% died before day: 967 969 0 %
90% died before day: 1073 1050 +2 %
Max lifespan observed (days) 1169 1212
Number of mice at start 48 93
Animal censor events are denoted by + marks in the plot
TJL – male
TJL – male      
NDGA effect on survival, males, test site = TJL
Log-rank test chisq = 2.8903 p = 0.0891
Wang-Allison test odds ratio = 2.1463 p = 0.1227
Quantiles NDGA Control % difference
25% died before day: 664 553 +20 %
Median lifespan (days) 846 757 +12 %
75% died before day: 927 875 +6 %
90% died before day: 1035 967 +7 %
Max lifespan observed (days) 1156 1216
Number of mice at start 57 125
Animal censor events are denoted by + marks in the plot
UM – female
UM – female      
NDGA effect on survival, females, test site = UM
Log-rank test chisq = 2.4271 p = 0.1193
Wang-Allison test odds ratio = 1.7294 p = 0.3673
Quantiles NDGA Control % difference
25% died before day: 802 772 +4 %
Median lifespan (days) 916 916 0 %
75% died before day: 1055 1005 +5 %
90% died before day: 1188 1111 +7 %
Max lifespan observed (days) 1249 1210
Number of mice at start 43 82
Animal censor events are denoted by + marks in the plot
UM – male
UM – male      
NDGA effect on survival, males, test site = UM
Log-rank test chisq = 1.5886 p = 0.2075
Wang-Allison test odds ratio = 1.266 p = 0.7906
Quantiles NDGA Control % difference
25% died before day: 776 727 +7 %
Median lifespan (days) 924 864 +7 %
75% died before day: 1052 995 +6 %
90% died before day: 1133 1121 +1 %
Max lifespan observed (days) 1267 1305
Number of mice at start 60 106
Animal censor events are denoted by + marks in the plot
UT – female
UT – female      
NDGA effect on survival, females, test site = UT
Log-rank test chisq = 0.7511 p = 0.3861
Wang-Allison test odds ratio = 0.4689 p = 0.386
Quantiles NDGA Control % difference
25% died before day: 719 744 -3 %
Median lifespan (days) 886 880 +1 %
75% died before day: 970 994 -2 %
90% died before day: 1051 1076 -2 %
Max lifespan observed (days) 1155 1188
Number of mice at start 48 96
Animal censor events are denoted by + marks in the plot
UT – male
UT – male      
NDGA effect on survival, males, test site = UT
Log-rank test chisq = 9.0875 p = 0.0026
Wang-Allison test odds ratio = 1.307 p = 0.5889
Quantiles NDGA Control % difference
25% died before day: 720 592 +22 %
Median lifespan (days) 858 739 +16 %
75% died before day: 974 877 +11 %
90% died before day: 1035 988 +5 %
Max lifespan observed (days) 1168 1132
Number of mice at start 52 119
Animal censor events are denoted by + marks in the plot


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Statistical definitions