An odds ratio of =
> 0.46 means that a treatment has halved the likelihood of something =
> happening....is that correct??

http://www.jr2.ox.ac.uk/bandolier/band25/b25-6.html

This explanation (Swot's corner: What is an odds ratio) is from Bandolier 
which is a very good site for evidence-based information.
Odds ratios are harder to understand (the odds in the treated or exposed 
group divided by the odds in the control group) than relative risk. An OR of 
0.46 means just that, whereas a Relative Risk of 0.46 means the risk is 
about halved.
When events are rare, there is little difference between ORs and RRs.
Most of the time people use these terms without being too precise about 
them.
Lisa Amir
MBBS, MMed, IBCLC in Melbourne, Australia 

             ***********************************************

To temporarily stop your subscription: set lactnet nomail
To start it again: set lactnet mail (or digest)
To unsubscribe: unsubscribe lactnet
All commands go to [log in to unmask]

The LACTNET mailing list is powered by L-Soft's renowned
LISTSERV(R) list management software together with L-Soft's LSMTP(R)
mailer for lightning fast mail delivery. For more information, go to:
http://www.lsoft.com/LISTSERV-powered.html