Many trials, particularly those for treatments of psychiatric disorders or pain, involve the use of human raters. This article looks at how human raters can contribute to apparently high placebo response rates. Drawing on his substantial experience as a board certified psychiatrist conducting clinical trials, Dr. Modell shares examples from his research as well as suggestions for minimizing problems.

This article includes discussion on:

• Factors that can skew trial patient populations and results
• Alternatives to human raters
• Training of research staff