treatments are still believed in. Perhaps, the maintenance of faith both in these interven-
tions and in the people carrying out the treatments suggests that they were actually
successful, giving the treatments themselves some validity. Why were they successful?
It is possible that there are medically active substances in some of these traditional
treatments that were not understood in the past and are still not understood now (e.g.
gladiators’ blood may actually contain some still unknown active chemical). It is also
possible that the effectiveness of some of these treatments can be understood in terms of
modern-day placebo effects.Modern-day placebos
Recently placebos have been studied more specifically and have been found to have a
multitude of effects. For example, placebos have been found to increase performance
on a cognitive task (Ross and Buckalew 1983), to be effective in reducing anxiety (Down-
ing and Rickles 1983), and Haas et al. (1959) listed a whole series of areas where
placebos have been shown to have some effect, such as allergies, asthma, cancer,
diabetes, enuresis, epilepsy, multiple sclerosis, insomnia, ulcers, obesity, acne, smoking
and dementia.
Perhaps one of the most studied areas in relation to placebo effects is pain. Beecher
(1955), in an early study of the specific effects of placebos in pain reduction, suggested
that 30 per cent of chronic pain sufferers show relief from a placebo when using both
subjective (e.g. ‘I feel less pain’) and objective (e.g. ‘You are more mobile’) measures of
pain. In addition, Diamond et al. (1960) reported a sham operation for patients suffering
from angina pain. They reported that half the subjects with angina pain were given a
sham operation, and half of the subjects were given a real heart bypass operation. The
results indicated that pain reduction in both groups was equal, and the authors
concluded that the belief that the individual had had an operation was sufficient to
cause pain reduction and alleviation of the angina.Placebos – to be taken out of an understanding of health?
Since the 1940s, research into the effectiveness of drugs has used randomized controlled
trials and placebos to assess the real effects of a drug versus the unreal effects. Placebos
have been seen as something to take out of the health equation. However, if placebos
have a multitude of effects as discussed above, perhaps, rather than being taken out they
should be seen as central to health status. For this reason it is interesting to examine how
placebos work.HOW DO PLACEBOS WORK?
If placebos have a multiple number of possible effects, what factors actually mediate
these changes? Several theories have been developed to try and understand the process
of placebo effects. These theories can be described as non-interactive theories in that they310 HEALTH PSYCHOLOGY