One in five respondents to a survey of physicians and psychiatrists in Canadian medical schools have administered or prescribed a placebo, researchers at McGill University have reported.

The survey, which was also designed to explore attitudes toward placebo use, found that the majority of responding psychiatrists (more than 60 per cent) believe that placebos can have therapeutic effects. This was a significantly higher proportion than for other medical practitioners.

More than 35 percent of the responding psychiatrists reported prescribing sub-therapeutic doses of medication (doses that are below, sometimes considerably below, the minimal recommended therapeutic level) to treat their patients.

Only 2 percent of the responding psychiatrists said that placebos have no clinical benefit at all. Psychiatrists seem to place more value in the influence placebos wield on the mind and body, the researchers said.

Ref: Raz A. et al., Placebos in Clinical Practice: Comparing Attitudes, Beliefs, and Patterns of Use between Academic Psychiatrists and Non-Psychiatrists, Canadian Journal of Psychiatry (accepted for 2011 publication)