ITP survival analysis:   L-leucine

Intervention:   L-leucine    
Trial code: Leu Dose: 40,000 ppm initiated at age: 5 mo Sex: both Cohort: C2017
Results are based on the use of pooled factor(s) that is/are stratified within the survival analysis model.

All test sites combined – female
Leu effect on survival, females, test site = All
Log-rank test chisq = 1.635 p = 0.201
Wang-Allison test odds ratio = 1.3842 p = 0.3908
Quantiles Leu Control % difference
25% died before day: 777 767 +1 %
Median lifespan (days) 853 868 -2 %
75% died before day: 968 958 +1 %
90% died before day: 1109 1060 +5 %
Max lifespan observed (days) 1285 1221
Number of mice at start 135 276
Animal censor events are denoted by + marks in the plot
All test sites combined – male
Leu effect on survival, males, test site = All
Log-rank test chisq = 1.2051 p = 0.2723
Wang-Allison test odds ratio = 0.7675 p = 0.5083
Quantiles Leu Control % difference
25% died before day: 477 447 +7 %
Median lifespan (days) 720 718 0 %
75% died before day: 865 919 -6 %
90% died before day: 1020 1029 -1 %
Max lifespan observed (days) 1180 1258
Number of mice at start 147 285
Animal censor events are denoted by + marks in the plot


By individual test site:

TJL – female
TJL – female      
Leu effect on survival, females, test site = TJL
Log-rank test chisq = 0.1793 p = 0.6719
Wang-Allison test odds ratio = 1.0 p = 1.0
Quantiles Leu Control % difference
25% died before day: 763 760 0 %
Median lifespan (days) 882 870 +1 %
75% died before day: 1013 968 +5 %
90% died before day: 1109 1068 +4 %
Max lifespan observed (days) 1177 1209
Number of mice at start 48 96
Animal censor events are denoted by + marks in the plot
TJL – male
TJL – male      
Leu effect on survival, males, test site = TJL
Log-rank test chisq = 0.6326 p = 0.4264
Wang-Allison test odds ratio = 0.43 p = 0.2656
Quantiles Leu Control % difference
25% died before day: 370 488 -24 %
Median lifespan (days) 718 748 -4 %
75% died before day: 972 949 +2 %
90% died before day: 1034 1079 -4 %
Max lifespan observed (days) 1139 1226
Number of mice at start 51 102
Animal censor events are denoted by + marks in the plot
UM – female
UM – female      
Leu effect on survival, females, test site = UM
Log-rank test chisq = 0.4863 p = 0.4856
Wang-Allison test odds ratio = 0.8217 p = 1.0
Quantiles Leu Control % difference
25% died before day: 766 820 -7 %
Median lifespan (days) 841 902 -7 %
75% died before day: 919 1000 -8 %
90% died before day: 1086 1098 -1 %
Max lifespan observed (days) 1285 1221
Number of mice at start 43 90
Animal censor events are denoted by + marks in the plot
UM – male
UM – male      
Leu effect on survival, males, test site = UM
Log-rank test chisq = 2.5839 p = 0.108
Wang-Allison test odds ratio = 0.7625 p = 0.7719
Quantiles Leu Control % difference
25% died before day: 505 468 +8 %
Median lifespan (days) 720 790 -9 %
75% died before day: 792 933 -15 %
90% died before day: 980 1019 -4 %
Max lifespan observed (days) 1180 1233
Number of mice at start 45 88
Animal censor events are denoted by + marks in the plot
UT – female
UT – female      
Leu effect on survival, females, test site = UT
Log-rank test chisq = 5.646 p = 0.0175
Wang-Allison test odds ratio = 3.0816 p = 0.0674
Quantiles Leu Control % difference
25% died before day: 791 696 +14 %
Median lifespan (days) 863 824 +5 %
75% died before day: 964 937 +3 %
90% died before day: 1112 993 +12 %
Max lifespan observed (days) 1280 1198
Number of mice at start 44 90
Animal censor events are denoted by + marks in the plot
UT – male
UT – male      
Leu effect on survival, males, test site = UT
Log-rank test chisq = 0.1424 p = 0.7059
Wang-Allison test odds ratio = 1.2719 p = 0.7762
Quantiles Leu Control % difference
25% died before day: 509 400 +27 %
Median lifespan (days) 723 676 +7 %
75% died before day: 859 825 +4 %
90% died before day: 979 963 +2 %
Max lifespan observed (days) 1171 1258
Number of mice at start 51 95
Animal censor events are denoted by + marks in the plot


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Statistical definitions