Search results

  1. 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...
  2. X

    How to draw cubic splines after Cox regression in Stata 11.1?

    Hi everyone:), In a cohort study, I would like to draw cubic splines, including HR and 95% CI, after Cox regression adjusted for age and sex. Yet, I have not found out the solution:confused:. Suppose that there are variables as follows: observetime, censor, variablex (the independent...
  3. X

    Some questions about one-way ANOVA in JMP 9

    One-way ANOVA can be used to estimate the contribution of a variable (x) to the variation in another one (y). I have some questions about it: 1. How to perform it in JMP 9? I am eager to get the R square. 2. Is this R square identical with the one by multivariate regression? 3. In ANOVA, is...