# st: Re: How to numerate different events from the same person?

 From "Michael Blasnik" To Subject st: Re: How to numerate different events from the same person? Date Thu, 13 Oct 2005 11:01:35 -0400

It appears that you don't really understand the difference between the -if- command and the -if- qualifier in Stata and need to read up on it. You may also want to try to learn more about subscripting. Perhaps most importantly, you should try to remember that any time you loop across the observations in a Stata dataset, you are probably making a mistake or making something more difficult than it needs to be. Rather than try to fix your code, I think you can get what you want from 1 line:

bysort patient: gen ing=_n

Michael Blasnik
michael.blasnik@verizon.net

----- Original Message ----- From: "Alejandro Allepuz" <aallepuz@aatrm.catsalut.net>
To: <statalist@hsphsun2.harvard.edu>
Sent: Thursday, October 13, 2005 10:44 AM
Subject: st: How to numerate different events from the same person?

I would like to assing to each discharge event of the same patient a number. The first discherge will be number 1, the second number 2 and so on.

This is the syntax I'm using. What's wrong with it? I don't know why local values remained unchange.

input patient diag
1 8151
1 8006
1 8153
2 8154
2 8155
3 8005
3 8155
end

gen lag_pat=patient[_n-1]
replace lag_pat=patient if lag_pat==.

gen ing=1
local j=1
local N=_N
forvalues i=1(1)`N'{
if (_n==`i' & patient==lag_pat) {
replace ing=`j'
local j=`j'+1
}
else local j=1
}

The result of this syntax was supposed to be:

+--------------------------------+
| patient diag lag_pat ing |
|--------------------------------|
1. | 1 8151 1 1 |
2. | 1 8006 1 2 |
3. | 1 8153 1 3 |
4. | 2 8154 1 1 |
5. | 2 8155 2 2 |
|--------------------------------|
6. | 3 8005 2 1 |
7. | 3 8155 3 2 |
+--------------------------------+

But I have obtained:

+--------------------------------+
| patient diag lag_pat ing |
|--------------------------------|
1. | 1 8151 1 1 |
2. | 1 8006 1 1 |
3. | 1 8153 1 1 |
4. | 2 8154 1 1 |
5. | 2 8155 2 1 |
|--------------------------------|
6. | 3 8005 2 1 |
7. | 3 8155 3 1 |
+--------------------------------+

Could anyboby help me?

Thanks a lot

Alejandro Allepuz Palau
*
*   For searches and help try:
*   http://www.stata.com/support/faqs/res/findit.html
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/