ITP survival analysis:   simvastatin

Intervention:   simvastatin     lipid-lowering drug
Trial code: Sim_lo Dose: 12 ppm initiated at age: 10 mo Sex: both Cohort: C2006
Trial code: Sim_hi Dose: 120 ppm initiated at age: 10 mo Sex: both Cohort: C2006
Results are based on the use of pooled factor(s) that is/are stratified within the survival analysis model.

All test sites combined – female
Sim_lo effect on survival, females, test site = All
Log-rank test chisq = 1.2608 p = 0.2615
Wang-Allison test odds ratio = 1.328 p = 0.4851
Quantiles Sim_lo Control % difference
25% died before day: 803 772 +4 %
Median lifespan (days) 916 882 +4 %
75% died before day: 1021 968 +5 %
90% died before day: 1088 1077 +1 %
Max lifespan observed (days) 1209 1261
Number of mice at start 142 237
Animal censor events are denoted by + marks in the plot
Sim_hi effect on survival, females, test site = All
Log-rank test chisq = 0.3526 p = 0.5526
Wang-Allison test odds ratio = 1.5339 p = 0.2212
Quantiles Sim_hi Control % difference
25% died before day: 748 772 -3 %
Median lifespan (days) 898 882 +2 %
75% died before day: 1015 968 +5 %
90% died before day: 1116 1077 +4 %
Max lifespan observed (days) 1357 1261
Number of mice at start 144 237
Animal censor events are denoted by + marks in the plot
All test sites combined – male
Sim_lo effect on survival, males, test site = All
Log-rank test chisq = 1.1571 p = 0.2821
Wang-Allison test odds ratio = 1.6611 p = 0.1105
Quantiles Sim_lo Control % difference
25% died before day: 673 650 +4 %
Median lifespan (days) 858 826 +4 %
75% died before day: 984 949 +4 %
90% died before day: 1081 1060 +2 %
Max lifespan observed (days) 1351 1268
Number of mice at start 166 309
Animal censor events are denoted by + marks in the plot
Sim_hi effect on survival, males, test site = All
Log-rank test chisq = 0.0 p = 0.9983
Wang-Allison test odds ratio = 1.6904 p = 0.1085
Quantiles Sim_hi Control % difference
25% died before day: 668 650 +3 %
Median lifespan (days) 789 826 -4 %
75% died before day: 940 949 -1 %
90% died before day: 1087 1060 +3 %
Max lifespan observed (days) 1385 1268
Number of mice at start 163 309
Animal censor events are denoted by + marks in the plot


By individual test site:

TJL – female
TJL – female      
Sim_lo effect on survival, females, test site = TJL
Log-rank test chisq = 0.7096 p = 0.3996
Wang-Allison test odds ratio = 0.4603 p = 0.3554
Quantiles Sim_lo Control % difference
25% died before day: 787 792 -1 %
Median lifespan (days) 892 888 0 %
75% died before day: 983 972 +1 %
90% died before day: 1032 1077 -4 %
Max lifespan observed (days) 1137 1261
Number of mice at start 46 68
Animal censor events are denoted by + marks in the plot
Sim_hi effect on survival, females, test site = TJL
Log-rank test chisq = 0.1132 p = 0.7365
Wang-Allison test odds ratio = 1.4711 p = 0.5495
Quantiles Sim_hi Control % difference
25% died before day: 732 792 -8 %
Median lifespan (days) 872 888 -2 %
75% died before day: 1004 972 +3 %
90% died before day: 1141 1077 +6 %
Max lifespan observed (days) 1357 1261
Number of mice at start 48 68
Animal censor events are denoted by + marks in the plot
TJL – male
TJL – male      
Sim_lo effect on survival, males, test site = TJL
Log-rank test chisq = 2.5882 p = 0.1077
Wang-Allison test odds ratio = 2.9777 p = 0.0555
Quantiles Sim_lo Control % difference
25% died before day: 670 633 +6 %
Median lifespan (days) 810 800 +1 %
75% died before day: 988 916 +8 %
90% died before day: 1082 1007 +7 %
Max lifespan observed (days) 1351 1197
Number of mice at start 60 96
Animal censor events are denoted by + marks in the plot
Sim_hi effect on survival, males, test site = TJL
Log-rank test chisq = 0.3833 p = 0.5359
Wang-Allison test odds ratio = 2.9777 p = 0.0555
Quantiles Sim_hi Control % difference
25% died before day: 602 633 -5 %
Median lifespan (days) 775 800 -3 %
75% died before day: 945 916 +3 %
90% died before day: 1107 1007 +10 %
Max lifespan observed (days) 1385 1197
Number of mice at start 60 96
Animal censor events are denoted by + marks in the plot
UM – female
UM – female      
Sim_lo effect on survival, females, test site = UM
Log-rank test chisq = 1.0676 p = 0.3015
Wang-Allison test odds ratio = 2.6786 p = 0.0851
Quantiles Sim_lo Control % difference
25% died before day: 765 788 -3 %
Median lifespan (days) 931 891 +4 %
75% died before day: 1042 990 +5 %
90% died before day: 1097 1069 +3 %
Max lifespan observed (days) 1200 1248
Number of mice at start 48 87
Animal censor events are denoted by + marks in the plot
Sim_hi effect on survival, females, test site = UM
Log-rank test chisq = 0.0679 p = 0.7945
Wang-Allison test odds ratio = 1.941 p = 0.2504
Quantiles Sim_hi Control % difference
25% died before day: 754 788 -4 %
Median lifespan (days) 894 891 0 %
75% died before day: 992 990 0 %
90% died before day: 1093 1069 +2 %
Max lifespan observed (days) 1185 1248
Number of mice at start 48 87
Animal censor events are denoted by + marks in the plot
UM – male
UM – male      
Sim_lo effect on survival, males, test site = UM
Log-rank test chisq = 0.1011 p = 0.7505
Wang-Allison test odds ratio = 1.2366 p = 0.781
Quantiles Sim_lo Control % difference
25% died before day: 736 701 +5 %
Median lifespan (days) 880 851 +3 %
75% died before day: 1018 974 +5 %
90% died before day: 1085 1077 +1 %
Max lifespan observed (days) 1202 1268
Number of mice at start 53 107
Animal censor events are denoted by + marks in the plot
Sim_hi effect on survival, males, test site = UM
Log-rank test chisq = 0.1367 p = 0.7116
Wang-Allison test odds ratio = 2.1196 p = 0.1689
Quantiles Sim_hi Control % difference
25% died before day: 698 701 0 %
Median lifespan (days) 880 851 +3 %
75% died before day: 964 974 -1 %
90% died before day: 1096 1077 +2 %
Max lifespan observed (days) 1267 1268
Number of mice at start 54 107
Animal censor events are denoted by + marks in the plot
UT – female
UT – female      
Sim_lo effect on survival, females, test site = UT
Log-rank test chisq = 2.6403 p = 0.1042
Wang-Allison test odds ratio = 1.5253 p = 0.5487
Quantiles Sim_lo Control % difference
25% died before day: 832 748 +11 %
Median lifespan (days) 934 843 +11 %
75% died before day: 1046 964 +9 %
90% died before day: 1118 1105 +1 %
Max lifespan observed (days) 1209 1192
Number of mice at start 48 82
Animal censor events are denoted by + marks in the plot
Sim_hi effect on survival, females, test site = UT
Log-rank test chisq = 1.1253 p = 0.2888
Wang-Allison test odds ratio = 1.2108 p = 0.7623
Quantiles Sim_hi Control % difference
25% died before day: 739 748 -1 %
Median lifespan (days) 919 843 +9 %
75% died before day: 1025 964 +6 %
90% died before day: 1119 1105 +1 %
Max lifespan observed (days) 1231 1192
Number of mice at start 48 82
Animal censor events are denoted by + marks in the plot
UT – male
UT – male      
Sim_lo effect on survival, males, test site = UT
Log-rank test chisq = 0.0076 p = 0.9304
Wang-Allison test odds ratio = 1.2239 p = 0.7817
Quantiles Sim_lo Control % difference
25% died before day: 631 586 +8 %
Median lifespan (days) 829 813 +2 %
75% died before day: 957 935 +2 %
90% died before day: 1061 1053 +1 %
Max lifespan observed (days) 1164 1212
Number of mice at start 53 106
Animal censor events are denoted by + marks in the plot
Sim_hi effect on survival, males, test site = UT
Log-rank test chisq = 1.1429 p = 0.285
Wang-Allison test odds ratio = 0.6978 p = 0.7773
Quantiles Sim_hi Control % difference
25% died before day: 619 586 +6 %
Median lifespan (days) 753 813 -7 %
75% died before day: 903 935 -3 %
90% died before day: 1031 1053 -2 %
Max lifespan observed (days) 1157 1212
Number of mice at start 49 106
Animal censor events are denoted by + marks in the plot


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Statistical definitions