larger studies with more subjects
are more significant than results from
smaller studies (all other factors being equal). Beware of small
studies claiming great significance !
control groups are better than ones
uThe P-value specifies the
probability of obtaining a result as or more or extreme than the result observed due to chance alone, so small P-values
(less than or <.05=5%) are good, but P<.01 is better !
uThe 95% confidence interval (CI) specifies a range for the (unknown) true result that is compatible with the
(known) observed result. It means that if a study could be repeated 100 times, the true result
would fall within the confidence interval 95% of the time.
uAn Odds Ratio (OR) is the odds of
a having particular outcome or disease given a particular exposure or other factor (such as a genetic
abnormality) compared to the odds
of having the same outcome without the exposure. An OR>1.5 is
usually considered significant, but >2 is very significant (it means the
odds in the exposed are TWICE those of the unexposed)