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Re: st: any virtues to stepwise regression?
At 09:44 08/08/2005, Svend Juul wrote:
If I was doing a data-mining exercise of this nature in an extensive
case-control study, then I think I would define a propensity score for each
candidate cause, calculate confidence limits and P-values for the
propensity-adjusted odds ratio for each candidate cause, and then use one
or more of the multiple test procedures available from the -smileplot-
package, downloadable from SSC (see Newson et al., 2003). This method would
have the advantage that I could then make meaningful confidence statements
about my set of "discoveries", which I could not do with a clear conscience
using stepwise regression.
Chris Ryan asked (rethorically?):
Are there *any* circumstances in which stepwise multiple regression
would be the preferred approach?
I can think of one example:
In the thalidomide disaster an epidemic of rare malformations occurred.
There were no strong, but dozens of weak hypotheses about the etiology.
In such a situation I think an extensive case-control study followed by
a stepwise logistic regression analysis is the most sensible thing to
Newson, R. and the ALSPAC Study Team. 2003. Multiple-test procedures and
smile plots. The Stata Journal 3(2): 109-132. A pre-publication draft is
downloadable from my website at http://www.kcl-phs.org.uk/rogernewson.
Lecturer in Medical Statistics
Department of Public Health Sciences
Division of Asthma, Allergy and Lung Biology
King's College London
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Opinions expressed are those of the author, not the institution.
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