“I beg farther to remark, if my theory and
pretensions, as to the nature, cause, and extent of the phenomena of
[hypnotism] have none of the fascinations of the transcendental to
captivate the lovers of the marvellous, the credulous and enthusiastic,
which the pretensions and alleged occult agency of the mesmerists have,
still I hope my views will not be the less acceptable to honest and
sober-minded men, because they are all level to our comprehension, and
reconcilable with well-known physiological and psychological
Braid, Hypnotic Therapeutics,
This booklet is designed to explain the concept of evidence-based
practice in relation to hypnotherapy and hypno-psychotherapy, and to
provide guidelines for therapists seeking to adopt a more evidence-based
By evidence we primarily mean information gained from credible
scientific research studies, including clinical trials and experimental
studies. An influential
definition was provided by Sackett
et al. (2000): “Evidence-based practice is the integration of best
research evidence with clinical expertise and patient values.”
A recent editorial in the
British Medical Journal defined Evidence-Based practice as follows,
Evidence based medicine is the conscientious, explicit, and judicious
use of current best evidence in making decisions about the care of
individual patients. The practice
of evidence based medicine means integrating individual clinical
expertise with the best available external clinical evidence from
The team of authors add the following remarks
regarding evidence-based practice in general medicine which, in our
view, apply equally well to the practice of hypno-psychotherapy,
Good doctors use both individual clinical expertise and the best
available external evidence, and neither alone is enough.
Without clinical expertise,
practice risks becoming tyrannised by evidence, for even excellent
external evidence may be inapplicable to or inappropriate for an
individual patient. Without
current best evidence, practice risks becoming rapidly out of date, to
the detriment of patients. (‘Evidence
based medicine: what it is and what it isn't’, Editorial, BMJ
As the founder of Cognitive Therapy, Aaron Beck, argues, to a large
extent scientific method can be seen as a refinement and extension of
ordinary “common sense.”
In his approach to external problems, man is a practical scientist: He
makes observations, sets up hypotheses, checks their validity, and
eventually forms generalisations that will later serve as a guide for
making rapid judgements of situations. […] Throughout his development,
man repeatedly uses the prototype of the experimental method –without
recognising it. (Beck, 1976:
Likewise, all therapists, necessarily, already formulate and check
hypotheses in their own, individual clinical practice.
Weitzenhoffer, one of the leading authorities on hypnotism,
Why this emphasis upon a scientific approach?
It is because the scientific method, which in many
instances, is just good plain common sense, has been found this far to
be the best available method, certainly the most suitable, for the
acquisition of useful, effective, knowledge.
(Weitzenhoffer, 2000: 18)
The Evidence-Based philosophy merely encourages clinicians to reflect on
this process and develop it to embrace more a sophisticated way of
interpreting the data of their own experience and that of others.
Clinical practice is fundamentally the applied branch of the science of
health. In view of the
success of the applied branches of other sciences, should we not
seriously consider an applied branch for the science of health along the
lines of the definitions just given?
Should that not then be what we as “clinicians” should practice?
Can any psychotherapist seriously consider carrying out her work
without giving due consideration to those scientifically established
facts that pertain to her practice?
(Weitzenhoffer, 2000: 19)
From the 1990s onward, “evidence-based” approaches to treatment have
become increasingly popular.
Increasingly, this trend is extending to the practice of psychotherapy
and hypnotherapy. The
official National Occupational Standards require hypnotherapists to be
competent in designing treatment plans based upon ‘evidence from
documented research and the success of the interventions concerned.’
(NOS, Element CH-H1.4). The
Standards also require hypnotherapists to know and understand ‘the
information available on effective complementary healthcare and how to
evaluate and use this information within [their] own practice.’ (NOS,
Knowledge & Understanding, E2-3.)
Do Therapists Intuitively Know What Works?
Sometimes therapists object that they can tell what
works and what doesn’t simply by observing their own experiences without
looking at other people’s research.
Personal clinical experience is an essential factor in deciding
how to help clients but there are other factors which need to be
Confirmation bias. There
is a well-documented tendency for people to look for evidence to support
their own presuppositions.
Therapists need to be careful to ask themselves whether they are
interpreting evidence in the way other people would, or being selective
in a way that merely confirms their own prejudices.
Failure to follow-up. It
is normal practice to measure the success of treatment after 6 weeks, 6
months, or even a year or more.
Therapists who base their judgement only on the feedback received
from clients during sessions, and not on long-term measures, are very
likely to statistically over-estimate the success of treatment as a
Absence of real-world exposure.
Some therapists carry out treatment without asking clients to
test their improvement out in the real world,
Clients may report feeling better in sessions but relapse when
they encounter the situations which previously triggered their problem.
For example, a phobic might not know how much improvement they
have made until they have tried to face their fears in reality, outside
of the consulting room.
Research consistently shows that many different forms of therapy have
broadly similar success rates, despite using an enormous variety of
theories and techniques. The
factors which psychological therapies have
in common, their
“non-specific” factors, are therefore likely to account for most of the
perceived benefits of treatment.
For example, clients’ expectations about improvement, emotional
support, therapist reassurance, etc., are such non-specific factors.
Therapists need to compare their success with a given technique
against meaningful baseline figures, therefore, in order to know whether
client improvement is due to the specific techniques used, or to
non-specific elements in the therapeutic relationship.
Assuming that a technique “works” simply because a client gets
better afterwards is known in philosophy of science as the
post hoc ergo propter hoc
fallacy, from the fact that someone gets better
after a therapy technique it does not follow that they got better
because of the therapy
Certain ways of measuring client improvement may mislead therapists.
In particular, over-dependence upon a single measurement of
client improvement, especially a single subjective measurement such as a
SUD (subjective units of disturbance) scale, may create exaggerated
estimates of client improvement.
In research, it is common practice to employ a battery of tests,
e.g., validated questionnaires, physiological measures, and observation
of behaviour change in order to arrive at a more reliable measurement of
a treatment’s effects.
Evidence-based practice doesn’t mean ignoring your own
personal observations, just being careful to interpret things as
objectively as possible, and acknowledging what other people have found
when they have carried out research in similar areas.
for Evidence-Based Hypno-Psychotherapy
There are a number of recommendations that can be made
to therapists seeking to adopt an Evidence-Based approach to their
Aim to interpret the practice of therapy primarily in terms
of credible, modern and mainstream scientific research, insofar as it is
possible to do so, e.g., in the fields of health science, psychology and
Occam’s Razor. Theories
should be avoided, or at least questioned, which depend upon reference
to pseudoscientific concepts or unnecessary/unverifiable hypotheses.
Psychotherapeutic theories, that is, should be consistent with
the law of scientific parsimony, or “Occam’s Razor”, which states:
“Entities are not to be multiplied without necessity.”
This principle requires that before new or controversial concepts
are introduced it must first be confirmed that established ones are
incapable of explaining the
phenomena in question. In
developing 19th century hypnotism, James Braid applied
Occam’s Razor by demonstrating that the new and controversial concept of
“animal magnetism” was unnecessary to explain the therapeutic
improvements and other effects observed.
Instead Braid demonstrated that “well-established” concepts like
expectation, imagination, suggestion, attention, habit formation, etc.,
were sufficient to account for the observable phenomena produced.
Hence Braid wrote, ‘There is, therefore, both positive and
negative proof in favour of my mental and suggestive theory, and in
opposition to the magnetic, occult, or electric theories of the
mesmerists and electro-biologists.
My theory, moreover, has this additional recommendation, that it
is level to our comprehension, and adequate to account for all which is
demonstrably true, without offering any violence to reason and common
sense, or being at variance with generally admitted physiological and
Utilise therapeutic techniques supported by a credible and comprehensive
interpretation of relevant research in this area, insofar as it is
reasonable and practicable to do so.
Eschew the use of techniques which have generally been shown to
lack empirical support, or which research has suggested may be harmful,
insofar as it is consistent with the well-being and best interests of
the client, and other ethical considerations, to do so.
Research Journals. Keep
abreast of current research in your field by subscribing to one of the
leading research journals, e.g.,
The International Journal for Clinical & Experimental Hypnosis
(IJCEH). These provide
essential information on the latest research studies reviews with
respect to the clinical practice of hypnotherapy.
Clinical Textbooks. It
is also important to study other contemporary sources of evidence-based
theory and practice, such as books published recently, i.e., within the
last ten years or so, and written by credible authors.
Credible psychotherapy textbooks should be expected to reference
a range of similar books and journal articles in their bibliography
section, and this can be taken as a rough indication of the breadth and
quality of research upon which they are based.
Well-established texts will often have gone through several
editions, such as the current 4th edition of
Hartland’s Medial & Dental
Hypnosis by Heap & Aravind.
The best hypno-psychotherapy textbooks are often quite specialist
hardback publications and may therefore be expensive.
Important textbooks are sometimes out of print, but most may be
easily obtained from large online booksellers.
Research Methods. Have
at least a basic understanding of psychotherapy and medical research
methods, sufficient to be able to interpret the meaning of articles in
contemporary research journals.
An understanding of the research issues relating to psychotherapy
and hypnotherapy will also help you to interpret the outcome of your own
Make use of formal clinical supervision to review your practice and
discuss the outcomes in relation to research in the field.
For instance, supervision offers an ideal opportunity to discuss
how research might guide clinical decisions you make with regard to the
interventions used to help a specific client.
Continual Professional Development (CPD).
All hypnotherapists should attempt to maintain their appreciation
of developments in the field through ongoing training and professional
development. This may
consist of attending high-quality CPD training or professional
Evidence-based practice is not meant to replace
clinical skill and experience but to supplement and inform it.
The interests of the client are paramount.
Every client, however, has the right to expect a high standard of
care from their therapist.
That includes the expectation that the therapist should be informed with
regard to research in his field, and basing his actions upon a
considered interpretation of credible scientific research.
One need not kowtow blindly to “science.”
Still, we must recognise that there is an implicit contract
between practitioners in psychology and psychiatry and the clients who
seek their help. This
involves the assumption that the techniques of mental health specialists
are based on scientific grounds. […] In this sense, it is a very
profound responsibility of the clinical practitioner that he be in
position to show some of the ties between what he practices and the
background of formal theory that makes up the body of knowledge in his
field. (Singer, 1974:
Please contact the Register for Evidence-Based
Hypnotherapy & Psychotherapy (REBHP) for further information or advice.
Cognitive Therapy & The Emotional
Electro-Biological Phenomena, etc.
Sackett, D. L., Straus, S. E., Richardson, W. S.,
Rosenberg, W., & Haynes, R. B. (2000).
Evidence based medicine:
How to practice and teach EBM, 2nd edition.
Imagery & Daydream Methods in
Psychotherapy & Behaviour Modification.
The Practice of Hypnotism.