As the doctor gone rogue

February 16, 2011

Working with date on Stata

Filed under: data management, STATA — Tags: , , — hypotheses @ 3:25 pm

Recently, I received a data coding date, for example, as 8/8/2011 for Aug 8, 2011. When importing this file into STATA, STATA automatically treated this as string. To be able to manipulate “date” easily, I converted it to numeric variable

gen int ndate = date(date, “MDY”)

Then for STATA to display this variable properly in a human readable format

format ndate %td

I, then, I have a question about the mid-visit date, which can now be easily calculated as

mean ndate if visit==2

This gave me number like 18302

Till now, the only way to find out what day this is for me is

display day(18342) month(18342) year(18342)

I think there might be an easier way to split out the DMY format, but I don’t know how yet.

For further information about working in date in STATA, I refer you to the resource on UCLA website, and help files in STATA.

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