Confounding.
BACKGROUND
Confounding is a statistical concept that is important to all researchers.


METHODS
The concept of confounding is explained with the help of an amusing but true example. Simple explanations about and examples of confounding are provided. Methods to deal with confounding are detailed and their applications and disadvantages are examined.


CONCLUSIONS
Attention to confounding is necessary at the time of study design as well as during the statistical analysis of data. The failure to identify and control for confounding can result in the faulty interpretation of study outcomes.
Andrade
Chittaranjan
C
Department of Psychopharmacology, National Institute of Mental Health and Neurosciences, Bangalore - 560 029, India.