st: generating matched set ID's after PSMATCH2

["Ariel Linden, DrPH" <ariel.linden@gmail.com>]

Hi All,

Perhaps someone has some code to generate IDs of matched sets after running
the user written program PSMATCH2?

More specifically, I'd like to generate grouped matches with an ID for all
matches within that set. So if there were 4 controls matched to 1 case, that
particular group should have a count of 5, and the same group ID should show
up 5 times. If 1 control was matched to 1 case, there should be two
individuals with the same group ID.

Thus, the final outcome would be to have a variable (called groupID)with a
sequential list of IDs (Starting at 1)representing all those cases and
controls within that matched set. In the example below (assuming 1 to 1
matching), tx = treatment, _id = the subject ID, _n1 = matched control ID,
and groupID is the id of both matched case and control. As you can see,
there are two of each groupID. 

Tx	_id 	_n1	groupID
1	1	6	1
1	2	7	2
1	3	8	3
1	4	9	4
1	5	10	5
0	6	.	1
0	7	.	2		
0	8	.	3
0	9	.	4
0	10	.	5

Thanks in advance!

Ariel

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