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The use of well controls: an unhealthy practice in psychiatric research

Published online by Cambridge University Press:  01 September 2010

S. Schwartz*
Affiliation:
Mailman School of Public Health, Columbia University, New York, NY, USA
E. Susser
Affiliation:
Mailman School of Public Health, Columbia University, New York, NY, USA New York State Psychiatric Institute, New York, NY, USA
*
*Address for correspondence: S. Schwartz, Ph.D., Mailman School of Public Health, Columbia University, 722 West 168th Street, Room 720b, New York, NY 10032, USA. (Email: [email protected])

Abstract

Background

Studies comparing cases with controls to uncover the causes of psychiatric disorders are common in biological research. The validity of these studies depends upon adherence to the methodological principles underlying the case-control design. However, these principles are often violated. One common practice that violates these principles is the use of well controls. In this paper we describe the bias that it can cause and discuss why the use of well controls leads to invalidity in case-control studies.

Method

Using hypothetical numerical examples we illustrate the consequences of using well controls.

Results

The results illustrate that the use of well controls can cause substantial bias. In no instance does the use of well controls improve validity.

Conclusions

We conclude that the use of well controls is an unhealthy practice in psychiatric research.

Type
Original Articles
Copyright
Copyright © Cambridge University Press 2010

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