I have data on survival time for breast cancer patients. Some of the covariates are missing. I would like to use multiple imputation. I have read a paper by White and Royston (Imputing missing covariates for the Cox model, Statistics in Medicine, 28 1982-1998) which discusses this issue at some length. They suggest first getting an estimate of the Nelson-Aalen cumulative hazard, which is done with sts gen haz = na and go on to say: "then the MICE algorithm is implemented by ice HT _d X* with appropriate options". I am not sure how to do this using mi impute chained. I have never used the ICE predecessor to mi impute and would appreciate some guidance as to how to proceed.
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