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Re: st: analysis of continuous gestational age
On 30 M�rta 2007, at 16:29, Ali Khashan wrote:
Dear all,
I am using a very large dataset (N=1.3m) to analyse the effect of a
categorical
variable on gestational age (continuous variable). I used linear
regression
(regress) but as you would probably expect the residuals are not
normally
distributed. I used qreg but the results do not look right.
Could anyone tell me what is the best analysis for continuous
gestational
please.
You need to tell us more about the data. Gestational age at delivery
will follow one sort of distribution, while gestational age recorded
at, say, ultrasound clinics will follow a multimodal distribution
that reflects the recommended schedule of clinic visits.
If you have gestational age worked out from ultrasonography, this can
be in days, which gives you a different data structure to the one you
get from clinical notes, which is usually in whole weeks.
So we can't say yet, but some more information may help.
=========
Ron�n Conroy
Royal College of Surgeons in Ireland
[email protected]
+353 (0) 1 402 2431
+353 (0) 87 799 97 95
http://www.flickr.com/photos/ronanconroy
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