Re: st: repeated measures

[Michael McCulloch <mm@pinestreetfoundation.org>]

Thanks Nick, you're correct I did misread that part.
Nevertheless, I suspect that some of the complexity you allude to your  
your prior reply to Michael E. is that he wishes to selectively carry  
forward certain field values. For example, something like:
	replace the missing value from (first visit at which it's available )  
if that value is present in that patient's first visit
I would know how to define the first visit a patient had, but not how  
to find the first visit at which a lab value appeared.
Michael

On Sep 7, 2010, at 1:12 PM, Nick Cox wrote:

> I think Michael M. is misreading this. It's a long to long mapping,  
> so -reshape- does not spring to mind here. See my earlier suggestions.
> Nick
> n.j.cox@durham.ac.uk
>
> Michael McCulloch
>
> This is possible with the -reshape- command. What you are starting
> with is the "long" data format, and you can use that command to change
> to "wide." However, there appear to be a few problems with your
> description:
> 1. Did you mean patient ID=4, not =3, in the last line of the data
> format you're seeking?
> 2. In the desired data format you list the "glu" data point for
> subject ID=3 as being from a different date than the original 6/1/09.
>
> On Sep 7, 2010, at 12:54 PM, Michael Eisenberg wrote:
>
> > I have a problem I hope you can help with that involves cleaning a
> > dataset for analysis.
> >
> > I have a dataset with about 10K men.  Several men had multiple clinic
> > visits, so that there are about 12K observations.  There is also some
> > lab data that I'll need that was not obtained until follow up visits.
> >
> > I would like to only analyze data from the earliest visit and the
> > first available lab data.
> >
> > Can stata do this?
> >
> >
> > Turn this
> >
> > patient     visitdate    sbp       dm          glu
> > 1              1/1/09       140       .             .
> > 1              1/4/09       128       .            202
> > 1              2/1/09       131      1            .
> >
> > 2              4/1/09       160      .             341
> > 2              4/4/09       144       .            180
> > 2              5/1/09       170      1            .
> >
> > 3              6/1/09       119       .             .
> > 3              6/4/09       107       .            .
> > 3              7/1/09       124      .            96
> >
> > 4              9/1/09       104       1          110
> > 4              9/4/09       155       .            .
> > 4             10/1/09       .         .              .
> >
> > Into this
> >
> > patient     visitdate    sbp       dm          glu
> > 1              1/1/09       140      1             202
> > 2              4/1/09       160      1            341
> > 3              6/1/09       119       .            96
> > 3              9/1/09       104      1            110
> *
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Best wishes,

Michael McCulloch, LAc MPH PhD
Pine Street Foundation
124 Pine Street
San Anselmo, CA 94960-2674
tel:	415-407-1357
fax: 	206-338-2391

*
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