How to use Clinical Evidence to inform
clinical decision making
A case study using the CE review on
generalised anxiety disorder
Generalised anxiety disorder
• Case history: 33-year-old man known to have
GAD presents to you, his GP, with increasing
anxiety. There is no specific trigger for, or focus
to, his anxiety, but it is now present for a
significant part of each day, and significantly
affecting his life
• He recognises his worries as irrational, but is
unable to control the anxiety
• He has presented to you and psychiatric services
in the past with similar problems but says the
situation has recently got worse
History
Case study constructed for purpose of
Clinical Evidence demonstration. Not
based on a patient seen by author, or on
any particular individual
• 33-year-old man, suffering from GAD for about 6 years
• Past medical history – depression for 9 months several
years ago
• Family history – mother has depression, brother has
alcohol dependence
• Social history – recently started a new job working as a
Sales Rep, involves driving daily for work, smokes 10
cigarettes per day, occasional moderate alcohol intake.
Previously had a good social life with friends, now
unable to socialise regularly due to GAD symptoms
The patient’s concerns…
• The patient explains he has tried diazepam before, and
this had some beneficial effects on his anxiety, but it
made him feel drowsy which means he could not drive
• He would be interested to find out if there are other
medications available, and is particularly concerned
about becoming ‘addicted’ to any medications
• He has found it difficult to take time off work to attend
this appointment and doesn’t want to have to book
more time off, as he does not want to have to explain
to new work colleagues about this issue
Issues to consider...
• How can his anxiety levels be reduced?
• SSRIs or benzodiazepines are commonly used
treatments, but how useful are they? He has tried
one drug in this class before, is it worth trying
another one? What about the side effects?
• Are there any non-pharmacological treatments
that would help?
• Which of these options are most appropriate for
this particular person?
• How strong is the evidence for these options?
Where to start?
• To use Clinical Evidence to find out what
evidence is available on GAD, begin by going
to the ‘Generalised anxiety disorder’ review
on the Clinical Evidence website
Further info on
the condition,
and on
treatment
guidelines
available here
Overview of
the treatments
for GAD, with
their
effectiveness
rating, for easy
comparison.
Click on a
treatment to
see the
evidence
behind these
categories
These are
the clinical
questions
we aim to
answer.
Navigation
here if you
just want to
quickly
browse
selected
parts of the
background
References
here to
related
resources if
you want
further
information,
or more
depth
Now you have more
background
knowledge, look
again at the
interventions and
their effectiveness.
From the available
evidence CBT
appears to be
Beneficial,
antidepressants
Likely to be
beneficial, whereas
other interventions
are not
From here, you decide to navigate on to CBT
You have
noticed that
CBT appears
to be
Beneficial, a
higher rating
than other
interventions.
As the patient
has no
treatment
preference
you decide to
find out more
about the
evidence base
behind this,
and begin by
reading the
Key Point
Symptom severity is
one of our outcomes of
interest
Navigating to
the CBT page,
we see the
benefits and
harms data.
Systematic
reviews or
individual
studies that
meet our
quality criteria
and investigate
clinically
important
outcomes are
reported in the
table
The quality of the evidence is
determined by the GRADE
score
Scrolling down
this page, we see
that relevant
systematic
reviews or RCTs
each have a line
in the table. The
table summarises
the population,
outcome, results,
and effect size,
and indicates
which
intervention is
favoured
So CBT is
compared
against other
interventions,
but the
outcomes of
interest are
the same
throughout
the review to
ensure that
you can
assess
consistently
how each
intervention
compares and
how it will
help your
patient
Systematic review or RCT
evidence is given the
maximum score of 4 points
Here we can see
the total
number of
participants and
studies that we
have included
for this outcome
and comparison
The overall GRADE score is obtained by adding the
numbers in the row. 4 points is high-quality evidence,
3 points moderate, 2 points low, etc
There are a
variety of
reasons why
points may be
deducted for
quality,
consistency, or
directness
reasons, and
these are
explained in the
final column
The GRADE
table.
This evaluates
all the
interventions
we have
included data
on for GAD
We have seen
the benefits
and harms of
CBT compared
with other
interventions.
Navigating
back to the
interventions
table we can
see what else
is available,
and how it is
rated
CE also
includes a
section on
Updates and
related
articles on
GAD
CE also
includes links
to guidelines
on the
management
of GAD. These
are not
limited to UK
guidelines
Patient concerns
• This patient has concerns about medication
affecting his ability to drive
• He is worried that he may become addicted to
medication
• He is worried that the waiting list for CBT may
take months
• He is worried that attending CBT will mean he
needs a lot of time off work. He wants to know
more about CBT, however, and whether there are
different approaches
Dealing with concerns…
• Do medications for GAD affect ability to drive?
• We can go to the interventions table in the review and click on each
of the medications to find out more. Unfortunately, all of the
medications that are ‘Beneficial’ (antidepressants, buspirone,
hydroxyzine, and pregabalin) can cause somnolence
• Are medications for GAD addictive?
• This isn’t covered by CE for most of the medications listed, as most
of the RCTs we found did not cover long-term effects. However, we
do point out that evidence from a non-systematic review showed
that benzodiazepines produce dependence. We therefore need to
look elsewhere for this information for the patient, bearing in mind
what we know from CE about interpreting research findings
Dealing with concerns…
• What are the waiting lists like for CBT?
• This is not covered by CE so we need to look
elsewhere for this information
• Do some psychological approaches need less time
commitment than others?
• In CE we cover CBT and applied relaxation.
However, we do not comment specifically on how
much time is needed for both techniques, so
again we need to look elsewhere for this, bearing
in mind what we know from CE about
interpreting research
Conclusions
• We have used CE to learn more about the
evidence behind different medical and
psychological approaches to the management of
GAD.
• We have used CE to compare these interventions
in terms of benefits and adverse effects
• We can use this information, in conjunction with
our knowledge of the patient’s condition and his
preferences, to advise him on an appropriate
treatment approach