Ziad wrote:
Any tips how to add (summation) 3 variables when one has empty value
(example below)
I did not want to use replace var=0 if var==. because i want to know
when all the 3 variables (ndrug1,ndrug2 and ndrug3 have empty values
at the same time)
id visitn ndrug1 ndrug2 ndrug3 total
------------------------------------------------------------------------
-----
1 2 . 2 1 3
1 4 2 . 3 5
1 8 2 3 3 8
1 12 . . . .
2 2 . . 2 2
2 4 1 1 . 2
===================================================================
. egen nonmiss = rownonmiss(ndrug*)
. egen total = rowtotal(ndrug*) if nonmiss>0
. list, clean
id visitn ndrug1 ndrug2 ndrug3 nonmiss total
1. 1 2 . 2 1 2 3
2. 1 4 2 . 3 2 5
3. 1 8 2 3 3 3 8
4. 1 12 . . . 0 .
5. 2 2 . . 2 1 2
6. 2 4 1 1 . 2 2
Hope this helps
Svend
__________________________________________
Svend Juul
Institut for Folkesundhed, Afdeling for Epidemiologi
(Institute of Public Health, Department of Epidemiology)
Vennelyst Boulevard 6
DK-8000 Aarhus C, Denmark
Phone: +45 8942 6090
Home: +45 8693 7796
Email: [email protected]
__________________________________________
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