

Disinfecting hand gels don't affect swine flu infection rate - cwan
http://www.physorg.com/news203533102.html

======
byoung2
The study revealed that only 42/100 from the group who used antibacterial hand
gel contracted rhinovirus infections vs 51/100 for the control group.
Similarly, 12 from the experimental group got swine flu vs 15 in the control
group. Wouldn't that suggest that the antibacterial hand gel had a measurable,
albeit small, effect?

~~~
btilly
Not exactly.

The headline is a classic example of how people misinterpret "insufficient
data to disprove the null hypothesis" as "evidence for the null hypothesis".

The truth is that from the data presented, we can't say much that is
statistically useful. They didn't measure an effect, and didn't disprove it
either. The one thing we learned is that the hand gel doesn't give an
overwhelming benefit.

However if they had followed 2 groups of 500 people and had a similar success
rate, they would have had overwhelming evidence that the gel helped a bit. Or
it they followed 2 groups of 500 people, they might have found a smaller
difference, and we could have this conversation again only with a smaller
possible effect and more data collected.

