A placebo is a “physiologically inert substance or sham intervention (psychological, physical or mechanical) which produces beneficial effects independent of any direct therapeutic effects”. The positive effects occur as a result of a patient’s expectations rather than as a result of a causative ingredient. A placebo can be for example be a saline solution, sterile water, or sham surgery.
The Placebo effect is a psychobiological response that influences clinical outcomes.[3] It refers to the positive outcomes that occur as a result of psychosocial factors and expectancies, rather than the intervention applied. It can occur when placebos are administered, but it can also enhance the effects of active interventions/substances.
