Dear Statalist,
First quickly “thanks” for this forum and all the stuff that is posted here - I have found many solutions over the years through the useful answers provided in this forum. I am currently looking into a new topic and would be grateful about some advice.
Dataset:
I am working with an epidemiological prospective cohort dataset that started in the 90’s in the UK with 25,000 individuals. The objective is to estimate the association between energy-intake from processed foods and incidence of CVD (failure event).
For each individual, I have two observations of the covariates. One, when the subject entered the study and the individual ‘baseline’ measurements were taken ("HealthCheck 1", between the years 93-98), and at a second time ("Health Check 2"between the years 98-2000). The outcomes are ascertained through hospital admission / health service registry records.
Analysis:
I want to perform Cox-regression with CVD as the event and want to take into account the changes of the covariates.
Issue:
I cannot figure out how to enter the time-varying covariates. The tvc - option of stcox doesn't really apply I think as my outcome is really not continous.
I looked at stsplit to split up the data, but figured that I cannot specify the date variable that would indicate the date of the second health check.
Does anyone have an idea how I can set up this analysis? Any hint / reference would be appreciated.
Thanks a lot in advance,
Kai.
First quickly “thanks” for this forum and all the stuff that is posted here - I have found many solutions over the years through the useful answers provided in this forum. I am currently looking into a new topic and would be grateful about some advice.
Dataset:
I am working with an epidemiological prospective cohort dataset that started in the 90’s in the UK with 25,000 individuals. The objective is to estimate the association between energy-intake from processed foods and incidence of CVD (failure event).
For each individual, I have two observations of the covariates. One, when the subject entered the study and the individual ‘baseline’ measurements were taken ("HealthCheck 1", between the years 93-98), and at a second time ("Health Check 2"between the years 98-2000). The outcomes are ascertained through hospital admission / health service registry records.
Analysis:
I want to perform Cox-regression with CVD as the event and want to take into account the changes of the covariates.
Issue:
I cannot figure out how to enter the time-varying covariates. The tvc - option of stcox doesn't really apply I think as my outcome is really not continous.
I looked at stsplit to split up the data, but figured that I cannot specify the date variable that would indicate the date of the second health check.
Does anyone have an idea how I can set up this analysis? Any hint / reference would be appreciated.
Thanks a lot in advance,
Kai.
