Strength of Evidence Empirically Supported Treatments

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Transcript Strength of Evidence Empirically Supported Treatments

Strength of Evidence;
Empirically Supported
Treatments
The Evidence Pyramid for
Treatment Effectiveness Questions
Clinical Trials – Phases of
Development
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Phase I: Researchers test a new drug or treatment in a small group of people for the
first time to evaluate its safety, determine a safe dosage range, and identify side
effects.
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Phase II: The drug or treatment is given to a larger group of people to see if it is
effective and to further evaluate its safety.
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Phase III: The drug or treatment is given to large groups of people to confirm its
effectiveness, monitor side effects, compare it to commonly used treatments, and
collect information that will allow the drug or treatment to be used safely.
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Phase IV: Studies are done after the drug or treatment has been marketed to gather
information on the drug's effect in various populations and any side effects associated
with long-term use.
Strength of Evidence
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Strength of research design: SR of
homogeneous studies at the highest level;
combines individual studies using a summary
metric
RCT strongest single research design capable of
demonstrating causation
Other key dimensions
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Consistency of evidence
Specificity
Dose-response
Biological or psychological plausability
Common sense
RCT Example - NRT
RCT Example – Buproprion v.
Placebo
Case Series and Case Reports
A group or series of case reports involving patients who were given similar
treatment. Reports of case series usually contain detailed information about
the individual patients. This includes demographic information (for example,
age, gender, ethnic origin) and information on diagnosis, treatment,
response to treatment, and follow-up after treatment.
Cohort Studies
Case Control Studies
The main advantages of case control studies are:
They can be done quickly. By asking patients about their past history, researchers can quickly discover
effects that otherwise would take many years to show themselves. Researchers don't need special
methods, control groups, etc. They just take the people who show up at their institution with a particular
condition and ask them a few questions. The first study to suggest a new medical conclusion will often be
a case control study, perhaps designed to check on a hypothesis suggested by a case series. If possible,
researchers will generally try to confirm the results with a randomized controlled trial or a cohort study.
Empirically Supported Treatments
in Psychology
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Let’s take a look at the Division 12
website:
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http://www.apa.org/divisions/div12/homepa
ge.html
Historical Aspects of EST
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TASK FORCE ON PROMOTION AND DISSEMINATION OF
PSYCHOLOGICAL PROCEDURES A Report Adopted by the
Division 12 Board - October 1993
Categories of support:
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I: supported by at least two RCT’s showing superiority to a palcebo or
other bonafide treatment
II: supported by at least one RCT showing superiority to a placebo or
other bonafide treatment, or some other reasonably well-controlled
situation
III: heterogeneous with low levels of evidence
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Current state of website:
http://www.apa.org/divisions/div12/est/chamble2.pdf
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Criticisms of EST
EST Criticisms
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EST’s used inappropriately in managed care
Malpractice for failure to follow guidelines
Practice restriction/restraint of trade
EST data is flawed
RCTism
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Manualization restricts generalization
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Rejects qualitative approach
Favors CBT
Limits application to specific cases
Not the way it happens in real life
Limited effectiveness data (as opposed to efficacy)