Re: st: Identifying unique values within duplicate IDs

[Rebecca Pope <rebecca.a.pope@gmail.com>]

I would just add to Jeph's suggestion:
bys ID (PHQ9) : gen byte tagged=(PHQ[1]!=PHQ[_N])*(_n==1)

This modification will only tag the first observation on an ID that
meets the condition of interest (PHQ 9 score changes). Then you can
just -list- the IDs.

-list ID if tagged, noobs clean-

Since you have a large dataset, you might want to -tab- the tagged
variable first and make sure that the list of duplicates whose scores
change isn't too long. If it will be, consider just saving it to a
file rather than just having it in the results window.

Regards,
Rebecca


On Wed, Mar 27, 2013 at 3:45 PM, Jeph Herrin <stata@spandrel.net> wrote:
>
> try
>
>  bys ID (PHQ9) : gen byte tagged=PHQ[1]!=PHQ[_N]
>
> cheers,
> Jeph
>
>
>
> On 3/27/2013 4:33 PM, Rebecca M Sacks wrote:
>>
>> Hi all!
>> I'm dealing with a large dataset that had some errors occur when data were being recorded. Although each ID should only
>> have one record, most of them have two. Anyway, I'm trying to get a list of IDs where the ID variable is a duplicate but
>> the values for a second variable (PHQ9 score) are different within the duplicate ID. Any advice would be greatly
>> appreciated.
>>
>> Thanks,
>> Rebecca Sacks
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