ITP survival analysis:   metformin

Intervention:   metformin     anti-diabetic, anti aging
Trial code: Met Dose: 1000 ppm initiated at age: 9 mo Sex: both Cohort: C2011
Results are based on the use of pooled factor(s) that is/are stratified within the survival analysis model.

All test sites combined – female
Met effect on survival, females, test site = All
Log-rank test chisq = 0.1241 p = 0.7246
Wang-Allison test odds ratio = 0.8259 p = 0.617
Quantiles Met Control % difference
25% died before day: 776 771 +1 %
Median lifespan (days) 872 873 0 %
75% died before day: 986 985 0 %
90% died before day: 1080 1089 -1 %
Max lifespan observed (days) 1259 1456
Number of mice at start 140 281
Animal censor events are denoted by + marks in the plot
All test sites combined – male
Met effect on survival, males, test site = All
Log-rank test chisq = 0.8817 p = 0.3477
Wang-Allison test odds ratio = 0.6957 p = 0.3236
Quantiles Met Control % difference
25% died before day: 650 595 +9 %
Median lifespan (days) 844 783 +8 %
75% died before day: 955 921 +4 %
90% died before day: 1044 1057 -1 %
Max lifespan observed (days) 1233 1258
Number of mice at start 148 294
Animal censor events are denoted by + marks in the plot


By individual test site:

TJL – female
TJL – female      
Met effect on survival, females, test site = TJL
Log-rank test chisq = 0.2318 p = 0.6302
Wang-Allison test odds ratio = 0.9885 p = 1.0
Quantiles Met Control % difference
25% died before day: 762 788 -3 %
Median lifespan (days) 867 892 -3 %
75% died before day: 1002 1015 -1 %
90% died before day: 1113 1106 +1 %
Max lifespan observed (days) 1259 1267
Number of mice at start 48 95
Animal censor events are denoted by + marks in the plot
TJL – male
TJL – male      
Met effect on survival, males, test site = TJL
Log-rank test chisq = 2.321 p = 0.1276
Wang-Allison test odds ratio = 1.1605 p = 0.7863
Quantiles Met Control % difference
25% died before day: 680 587 +16 %
Median lifespan (days) 859 763 +13 %
75% died before day: 980 886 +11 %
90% died before day: 1093 1057 +3 %
Max lifespan observed (days) 1209 1258
Number of mice at start 53 101
Animal censor events are denoted by + marks in the plot
UM – female
UM – female      
Met effect on survival, females, test site = UM
Log-rank test chisq = 0.1981 p = 0.6563
Wang-Allison test odds ratio = 1.3305 p = 0.5803
Quantiles Met Control % difference
25% died before day: 796 750 +6 %
Median lifespan (days) 864 872 -1 %
75% died before day: 1005 979 +3 %
90% died before day: 1142 1081 +6 %
Max lifespan observed (days) 1254 1456
Number of mice at start 49 95
Animal censor events are denoted by + marks in the plot
UM – male
UM – male      
Met effect on survival, males, test site = UM
Log-rank test chisq = 0.1627 p = 0.6866
Wang-Allison test odds ratio = 0.3021 p = 0.1406
Quantiles Met Control % difference
25% died before day: 708 712 -1 %
Median lifespan (days) 855 860 -1 %
75% died before day: 1019 983 +4 %
90% died before day: 1061 1121 -5 %
Max lifespan observed (days) 1233 1251
Number of mice at start 47 94
Animal censor events are denoted by + marks in the plot
UT – female
UT – female      
Met effect on survival, females, test site = UT
Log-rank test chisq = 0.3894 p = 0.5326
Wang-Allison test odds ratio = 0.3234 p = 0.2246
Quantiles Met Control % difference
25% died before day: 779 754 +3 %
Median lifespan (days) 884 857 +3 %
75% died before day: 977 977 0 %
90% died before day: 1026 1089 -6 %
Max lifespan observed (days) 1078 1301
Number of mice at start 43 91
Animal censor events are denoted by + marks in the plot
UT – male
UT – male      
Met effect on survival, males, test site = UT
Log-rank test chisq = 0.1689 p = 0.6811
Wang-Allison test odds ratio = 0.7288 p = 0.7742
Quantiles Met Control % difference
25% died before day: 586 542 +8 %
Median lifespan (days) 790 715 +10 %
75% died before day: 902 857 +5 %
90% died before day: 985 1013 -3 %
Max lifespan observed (days) 1099 1186
Number of mice at start 48 99
Animal censor events are denoted by + marks in the plot


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Statistical definitions