Blinding in exercise studies is difficult because placebo controls for
exercise are difficult, if not impossible given the requirement of
informed consent. There are different ways around this and still have high
quality evidence for exercise:
1. Use an active control instead of a (usually botched placeboš) control
(see http://www.ncbi.nlm.nih.gov/pubmed/19998192 for discussion).
2. Do a dose-responseš study (see http://cebp.nl/media/m1121.pdf for an
example of this).
Unfortunately adequate placebo controls are much more difficult to design
than they are to talk about ...
Jeremy Howick PhD
Centre for Evidence-Based Medicine
Department of Primary Care Health Sciences
University of Oxford
New Radcliffe House, 2nd floor
Jericho, OX2 6NW
On 16/02/2015 23:18, "Anoop Balachandran" <[log in to unmask]> wrote:
>I had a question regarding blinding outcome assessors.
>Can I have different testers for testing people during pre test and post
>test? Or does it have to be the same people?
>I am planning to use the testers who did the pre-test to do the training
>too. And getting different testers for post-test who are blind to the
>group allocation or haven't seen the subjects train.
>Any thoughts please
>Thank you so much,