ITP survival analysis:   methylene blue

Intervention:   methylene blue     agent that protects against oxidative damage
Trial code: MB Dose: 28 ppm initiated at age: 4 mo Sex: both Cohort: C2009
Results are based on the use of pooled factor(s) that is/are stratified within the survival analysis model.

All test sites combined – female
MB effect on survival, females, test site = All
Log-rank test chisq = 2.2492 p = 0.1337
Wang-Allison test odds ratio = 2.5698 p = 0.0074
Quantiles MB Control % difference
25% died before day: 785 778 +1 %
Median lifespan (days) 902 881 +2 %
75% died before day: 1026 988 +4 %
90% died before day: 1133 1066 +6 %
Max lifespan observed (days) 1224 1229
Number of mice at start 135 242
Animal censor events are denoted by + marks in the plot
All test sites combined – male
MB effect on survival, males, test site = All
Log-rank test chisq = 1.3409 p = 0.2469
Wang-Allison test odds ratio = 0.8037 p = 0.6173
Quantiles MB Control % difference
25% died before day: 579 616 -6 %
Median lifespan (days) 788 807 -2 %
75% died before day: 922 973 -5 %
90% died before day: 1037 1094 -5 %
Max lifespan observed (days) 1291 1338
Number of mice at start 146 295
Animal censor events are denoted by + marks in the plot


By individual test site:

TJL – female
TJL – female      
MB effect on survival, females, test site = TJL
Log-rank test chisq = 0.0752 p = 0.784
Wang-Allison test odds ratio = 1.6025 p = 0.5298
Quantiles MB Control % difference
25% died before day: 785 768 +2 %
Median lifespan (days) 862 894 -4 %
75% died before day: 986 976 +1 %
90% died before day: 1121 1051 +7 %
Max lifespan observed (days) 1224 1197
Number of mice at start 47 60
Animal censor events are denoted by + marks in the plot
TJL – male
TJL – male      
MB effect on survival, males, test site = TJL
Log-rank test chisq = 3.0882 p = 0.0789
Wang-Allison test odds ratio = 0.4003 p = 0.1783
Quantiles MB Control % difference
25% died before day: 543 606 -10 %
Median lifespan (days) 701 807 -13 %
75% died before day: 877 941 -7 %
90% died before day: 1009 1061 -5 %
Max lifespan observed (days) 1100 1338
Number of mice at start 54 101
Animal censor events are denoted by + marks in the plot
UM – female
UM – female      
MB effect on survival, females, test site = UM
Log-rank test chisq = 4.0941 p = 0.043
Wang-Allison test odds ratio = 6.2244 p = 0.0021
Quantiles MB Control % difference
25% died before day: 848 797 +6 %
Median lifespan (days) 996 886 +12 %
75% died before day: 1084 1008 +8 %
90% died before day: 1159 1088 +7 %
Max lifespan observed (days) 1210 1229
Number of mice at start 44 90
Animal censor events are denoted by + marks in the plot
UM – male
UM – male      
MB effect on survival, males, test site = UM
Log-rank test chisq = 0.0574 p = 0.8107
Wang-Allison test odds ratio = 1.3243 p = 0.7592
Quantiles MB Control % difference
25% died before day: 798 742 +8 %
Median lifespan (days) 905 925 -2 %
75% died before day: 987 1077 -8 %
90% died before day: 1157 1151 +1 %
Max lifespan observed (days) 1291 1325
Number of mice at start 41 95
Animal censor events are denoted by + marks in the plot
UT – female
UT – female      
MB effect on survival, females, test site = UT
Log-rank test chisq = 0.0487 p = 0.8253
Wang-Allison test odds ratio = 1.6514 p = 0.3802
Quantiles MB Control % difference
25% died before day: 779 750 +4 %
Median lifespan (days) 884 866 +2 %
75% died before day: 993 994 0 %
90% died before day: 1075 1062 +1 %
Max lifespan observed (days) 1190 1213
Number of mice at start 44 92
Animal censor events are denoted by + marks in the plot
UT – male
UT – male      
MB effect on survival, males, test site = UT
Log-rank test chisq = 0.0002 p = 0.9901
Wang-Allison test odds ratio = 0.9676 p = 1.0
Quantiles MB Control % difference
25% died before day: 529 497 +6 %
Median lifespan (days) 699 704 -1 %
75% died before day: 867 903 -4 %
90% died before day: 980 1013 -3 %
Max lifespan observed (days) 1172 1133
Number of mice at start 51 99
Animal censor events are denoted by + marks in the plot


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Statistical definitions