Diego wrote
I have to perform a test for categorical variables stratified
by the groups of patients I have (two groups).
I thought to use McNemar for that, but to perform a stratified
categorical analysis I should use Mantel-Haenzel (is that
correct) ?
I tried to use McNemar (mcc command) with the "by" option but
it does not accept it.
So the question : how could I perform a stratified McNemar test
for paired categorical data ?
-------------------------------------------------------
I may misunderstand your description, but if this is correct:
1. The outcome is dichotomous, like dead/alive
2. You have matched pairs of patients, one exposed to A, the
other to B
3. Your patient-pairs fall in two groups, e.g. living in two
different areas og suffering two different diseases (X and Y).
4. The two patients in a matched pair come from the same group
(X or Y).
then you can make a standard matched analysis (-mcc-) because
due to the matching principle the two groups (X and Y) are not
mixed up.
You may, however, be interested in any differences in effect
between group X and Y. In that case you could make separate
-mcc- analyses for the two groups. Another option is conditional
logistic regression (-clogit-).
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, work: +45 8942 6090
Phone, home: +45 8693 7796
Fax: +45 8613 1580
E-mail: [email protected]
_________________________________________________________
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