Forwarded for Jennifer Marino.
Nick
[email protected]
-----Original Message-----
From: Marino, Jennifer [mailto:[email protected]]
As part of my dissertation in epidemiology, I have case-control study
occupational data that have left me baffled. I have work histories for
cases and controls, with one record per respondent, thus:
id jobcode1 industrycode1 firstyear1 lastyear1 jobcode2 industrycode2
firstyear2 lastyear2 . . .
so the record for a respondent who worked as a bank teller from 1979 to
1985 and then as a bank manager from 1985 to 1990 would look like this
id jobcode1 indcode1 firstyr1 lastyr1 jobcode2
indcode2 firstyr2 lastyr2 . . .
31040-70 383 702 1979 1985 019 702 1985
1990 . . .
I need to figure out duration within job class as a predictor for
case/control status. "forvalues" has come in handy to make job classes
out of job and industry codes, for example:
*engineers, architects, draughtsmen
forvalues i = 1/16{
gen tempjobnum`i'=jobnum`i'
replace tempjobnum`i'=. if (jobnum`i'==185 & indnum`i'==681)
}
egen engarchdra=eqany(tempjobnum*),v(043 044 046 049 053 055 to 057 059
127 173 185 217) drop tempjobnum*
But I can't figure out how to get at duration in a certain job class,
especially since jobs may overlap within (or outside) class or even job
code. For the example above, if the respondent had worked her main job
as a bank teller for Bank of Mystery from 1983 to 1989, but had worked
part-time as a bank teller at First Bank of Other from 1983 to 1987, she
would actually have worked in that job class (and job code) for ten
years, but summing her years would overestimate her time worked as 10
years. I have the idea that creating a flag variable for such overlap
using the same kind of indexed "forvalues" syntax is the way to go, but
I'm not at all sure how to go about using the flag, especially since the
job class is conditioned on the industry class.
I tried thinking about it from the perspective described in the FAQ "How
do I convert my spell-type data into a survival dataset?" but of course
there's no failure event in case-control data. Please forgive me if I'm
missing an obvious source of this information - I've looked through the
manuals and archives, but I may be looking the wrong way, in which case
a redirect would be much appreciated. Oh, and I'm still using STATA8
because changing versions mid-analysis is kind of scary, but I'm open to
it if my answers lie there.
Thanks very much,
Jennifer Marino
University of Washington &
Fred Hutchinson Cancer Research Center
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