time to event

  1. M

    Cox Proportional Hazards Regression

    Hi, I am hoping someone can help me with which model (frailty, strata or cluster) I should use for my data. I have paired data so I need to take that into account when modelling the Cox PH Regression and am unsure which model will give me a more accurate result. My study was looking at the...
  2. X

    How to use instrumental variable to estimate hazard ratios and 95% CI?

    Hi, I am doing a Mendelian randomization analysis, by using an instrumental variable (Z, which is the genotype of exposure variable X), to investigate whether there is a causal association of genetically determined X on survival (Y). Suppose that Y includes information of both a dichotomized...
  3. B

    Unblinding Concern: Projecting Last Event in > 2 Arm Study....

    In a two arm time to event study one can use various blinded projection methods using the aggregate event rate to estimate when the last event may occur. Now, lets say one has a three arm study where two different doses of an experimental drug are compared to a control. In addition each...