Hello,
Am new to this topic so I will appreciate any feedback.
I am to analyze the efficacy endpoint that include the occurrence of an infection between the last vaccination and the subsequent 168 days (2 month) and separately for the subsequent 532 (5 month) days if efficacy is shown for the initial follow-up period. The number censored are small, say < 10%, so I think the resulting bias is likely to be small and can be ignored (Please let me know any other thoughts).
Question1: I have these following dates but am not sure which ones I’ll use to calculate my survival time.
SubjectReferenceStartDate SubjectReferenceEndDate DateofFirstStudyTreatment DateofLastStudyTreatment DateofEndofParticipation.
Question 2: How do I create a variables e.g. XYZ and that will be use in the TIME statement in PROC LIFETEST calculation ?
For example:
proc lifetest data= A notable;
time survtime*censor(0);
strata treat;
run;
I have created this artificial data with variable of interest to help demonstrate my idea and I included the dates in the first few encounter.
subjectID $ Age ArmCode $ SubjectReferenceStartDate SubjectReferenceEndDate DateofFirstStudyTreatment DateofLastStudyTreatment DateofEndofParticipation Result $ VisitName $
AB123 30 Drug 2015-03-01 2017-12-01 2015-03-01 2015-06-27 2017-12-01 Negative Day 10, Dose 3
AB123 30 Drug 2015-03-01 2017-12-01 2015-03-01 2015-06-27 2017-12-01 Negative Month 1, Post-dose 3
AB123 30 Drug 2015-03-01 2017-12-01 2015-03-01 2015-06-27 2017-12-01 Positive Month 2, Post-dose 3
AB123 30 Drug 2015-03-01 2017-12-01 2015-03-01 2015-06-27 2017-12-01 Negative Month 3, Post-dose 3
AB123 30 Drug 2015-03-01 2017-12-01 2015-03-01 2015-06-27 2017-12-01 Negative Month 4, Post-dose 3
AB123 30 Drug 2015-03-01 2017-12-01 2015-03-01 2015-06-27 2017-12-01 Positive Month 5, Post-dose 3
AB123 30 Drug 2015-03-01 2017-12-01 2015-03-01 2015-06-27 2017-12-01 Positive Month 6, Post-dose 3
AB123 30 Drug 2015-03-01 2017-12-01 2015-03-01 2015-06-27 2017-12-01 Positive Month 7, Post-dose 3
CD456 35 Placebo 2015-03-01 2017-12-01 2015-03-01 2015-06-27 2017-12-01 Negative Day 10, Dose 3
CD456 35 Placebo Negative Month 1, Post-dose 3
CD456 35 Placebo Negative Month 2, Post-dose 3
CD456 35 Placebo Positive Month 3, Post-dose 3
CD456 35 Placebo Negative Month 4, Post-dose 3
CD456 35 Placebo Negative Month 5, Post-dose 3
CD456 35 Placebo Negative Month 6, Post-dose 3
CD456 35 Placebo Positive Month 7, Post-dose 3
CD456 35 Placebo Negative Month 8, Post-dose 3
YZ789 25 Placebo Negative Month 1, Post-dose 3
YZ789 25 Placebo Negative Month 2, Post-dose 3
YZ789 25 Placebo Negative Month 3, Post-dose 3
YZ789 25 Placebo Negative Month 4, Post-dose 3
YZ789 25 Placebo Negative Month 5, Post-dose 3
YZ789 25 Placebo Negative Month 6, Post-dose 3
YZ789 25 Placebo Negative Month 7, Post-dose 3
YZ789 25 Placebo Negative Month 8, Post-dose 3
EF456 33 Drug Negative Day 10, Dose 3
EF456 33 Drug Negative Month 1, Post-dose 3
EF456 33 Drug Negative Month 2, Post-dose 3
EF456 33 Drug Negative Month 3, Post-dose 3
EF456 33 Drug Negative Month 4, Post-dose 3
EF456 33 Drug Positive Month 5, Post-dose 3
EF456 33 Drug Negative Month 6, Post-dose 3
