PSYCHOLOGY AND PHYSICAL THERAPY

POTENTIAL FOR THE USE OF PLACEB (PART I)

By Dr Chris Beedie PhD and James Hopker BSc.

It is incumbent on all professional practitioners to acknowl- edge theoretical and technological developments in their field. In keeping with this ethos, it is fair to suggest that the majority of physical therapists are keen to utilise recent improvements in related techniques and technology. Often neglected by physical therapists however are developments in the field of human thought and behaviour, areas often deemed the realm of the sports or clinical psychologist. Such neglect may have a significant impact on the effectiveness of physical therapies. Research in medicine and clinical psychology is increasingly indicating that psychological processes may be significant factors in physical therapy, especially in relation to pain, inflamma- tion and healing. In this two-part article, we outline evidence that suggests how one psychological phenomenon, belief, may act synergistically with pharmacological/ physical treatments – or even in the absence of pharmaco- logical/physical treatments – to influence patient outcomes. This phenomenon is termed the placebo effect.

The placebo effect is a favourable outcome arising from a patient’s belief that they have received a beneficial treatment. A placebo is any therapy or component of a therapy that is deliberately used for its non-specific, psychological or psychophysiological effect. Despite much anecdotal and experi- mental evidence for such belief ‘effects’ (1), the placebo effect is still considered controversial and counter-intuitive by many prac- titioners. The placebo effect is however well recognised in many areas of science, for example, through the requirement that all new drugs be tested in double-blind placebo-controlled trials (2). Such placebo-controlled methodologies ensure that the biological effects of the drug under examination exceed any treatment effects attributable to psychological processes. This requirement alone indicates that the medical and scientific communities recognise the power of psychological processes to act synergisti- cally, or even in the absence of, pharmacologically active drugs and treatments. A recent search of the MEDLINE database revealed over 12,000 articles published between 1966 and 2005 with the words ‘placebo controlled’ in the title. It has also been argued that the placebo effect is frequently, and sometimes inadvertently, utilised as a direct therapeutic intervention, for example, the common, and often successful, practice of prescribing antibiotics for viral infections (3).

The potential for the effective use of placebos is somewhat para- doxical, and to many practitioners seems ethically problematic. If a patient is deceived, that is, informed they are taking an active substance when they are not, the treatment may be effective. However, if the patient is told the truth, that is, correctly informed they are taking an inactive substance, the treatment will almost certainly be worthless. Despite this, as will be demon- strated below, compelling evidence does suggest that positive health outcomes can occur without a pharmacologically active treatment being administered, and without the practitioner needing

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