[EpiData-list] OR error report

epidata-list at lists.umanitoba.ca epidata-list at lists.umanitoba.ca
Tue Oct 14 07:01:53 CDT 2008

I did not mean to suggest that EpiData follows choices made in OpenEpi - 
that's just an easy way to see the differences between the two 
estimates. One of the very nice features of EpiData is that the screen 
is not cluttered by having multiple results. This is why you have to ask 
for OR or RR in the command--based on your knowledge of study design. 
Getting multiple odds ratio estimates AND an estimate of relative risk 
is confusing to many users. Why not go with the 'best' estimator rather 
than the one that is computationally easiest?

Mid-p estimates make sense to me (as a statistician in my past life), 
but they haven't gained favour in the main stream yet.

Thanks for comments - I know that the development team finds this kind 
of feedback useful because I have seen some of my own suggestions 


> I would like EpiData Analysis to state that its OR is CMLE (at least in the existing help file).
> AND add (regular) OR as well if you may, because both are there in OpenEpi.
> If you follow OpenEpi I wonder why you use Fisherexact p only instead of Mid-P Exact as well(Mid-P Exact is the preferred by the author(s) at OpenEpi by the way in this case).
> By the way, EpiInfo 6 Statcalc calculates OR not by CMLE and obtains
> same as SPSS does.
>> Subject: Re: [EpiData-list] OR error report
>> Date: Monday, October 13, 2008, 7:09 PM
>> EpiData provides the conditional maximum likelihood estimate
>> for OR, 
>> which is normally accepted as a better estimate.
>> If you put your data into OpenEpi you can see the
>> differences between 
>> estimates and confidence intervals:
>> http://www.openepi.com/
>> Jamie

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