Create table by using a tag from duplicates command

[Vilma Antonov]

Hi,

I have tried to google my best and search the forum but I can't seem to find something regarding my (very simple, I'm afraid) problem.

I have a large dataset where some observations have the same ID-number (aka one patient have two observations). To find these, I have used the duplicates command, and created a new variable:

duplicates tag ID_CODE, generate(tags)

I have found 150 duplicates.

I would now like to create a table with the duplicates (I figured I could do that by using the new tags-variable) and the date (variable DATE) the observation was made, creating a table with the ID_CODE and DATE of all duplicates displayed.
Sadly, my Stata-knowledge doesn't seem to get me there

Any advice would be greatly appreciated!

[Nick Cox]

Is

tab ID_CODE if tags

what you want?

[Vilma Antonov]

Thanks for your quick response! Yes, partly, but I would like to have ID_CODE and DATE in the same table.

[Nick Cox]

groups ID_CODE DATE if tags

where groups is downloadable via

. search st0496, entry

Search of official help files, FAQs, Examples, and Stata Journals

SJ-18-1 st0496_1  . . . . . . . . . . . . . . . . . Software update for groups
        (help groups if installed)  . . . . . . . . . . . . . . . .  N. J. Cox
        Q1/18   SJ 18(1):291
        groups exited with an error message if weights were specified;
        this has been corrected

SJ-17-3 st0496  . . . . .  Speaking Stata: Tables as lists: The groups command
        (help groups if installed)  . . . . . . . . . . . . . . . .  N. J. Cox
        Q3/17   SJ 17(3):760--773
        presents command for listing group frequencies and percents and
        cumulations thereof; for various subsetting and ordering by
        frequencies, percents, and so on; for reordering of columns;
        and for saving tabulated data to new datasets

Download from st0496_1 but read st0496's paper or https://www.statalist.org/forums/for...updated-on-ssc if more details are needed.

[Vilma Antonov]

Nick, thank you so much! This worked perfectly!