Paul's comment prompted me to remind myself what the Bradford Hill guidelines
are --- google found this paper with a clear explanation of the 9 Bradford Hill
criteria AND (which especially interested me) the limits of their application.
The Bradford Hill considerations on causality: a counterfactual perspective
by Michael Höfler.
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1291382#B3
Michael
Dr Michael Power BSc Hons, MB BCh, MD, DCH
Clinical Knowledge Author, Guideline Developer and Informatician
Clinical Knowledge Summaries Service www.cks.library.nhs.uk
Sowerby Centre for Health Informatics at Newcastle Ltd www.schin.co.uk
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On Mon, 15 Sep 2008 15:29:46 +0100, Paul Glasziou
<[log in to unmask]> wrote:
>Good points Cristian and Christian,
>So maybe we should distinguish between factors (causal) and markers.
>Hence there would be:
>1. risk factors such as blood pressure, smoking and BrCa1
>2. risk markers such as an ear lobe crease
>3. prognostic factors such as smoking
>4. prognostic markers such as Gleeson score
>This is a conceptual distinction as it is often difficult to tell if
>something is a causal factor or a marker
>(Hence the Bradford-Hill guidelines)
>Cheers
>Paul Glasziou
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