Lecture notes Evidence-Based Interventions (PSMKB-1)

Lecture notes Evidence-based interventions (PSMKB-1)
Learning goals of course;

1. can articulate the basic principles of evidence based mental health and can articulate the
research methodology for validating psychological treatments
2. can search literature for evidence-based-treatments when confronted with a clinical case
3. can articulate what a clinical guideline is and how it is used in individual treatment
4. can articulate what a treatment protocol is and how these are used in clinical practice
5. can provide arguments to convince practitioners to implement a specific evidence-based
treatment in their setting



Lecture 1: Introduction and finding evidence: sources
Learning objectives for today;

- Learning how to search for scientific evidence
- Learning how to formulate a clinical question
- Learning how to appraise the quality of scientific evidence and
methods for improving quality
- Knowing about possible biases in published evidence

Evidence based medicine: “integrating individual clinical expertise with
the best available external clinical evidence from systematic research.”




Searching for scientific evidence;

- Scientific data bases
 University library: PsychInfo and PsychArticles (including APA journals) & Medline –
Pubmed (option: clinical queries)
 Cochrane library: Systematic reviews and meta-analyses

Search within databases: PICO framework

- Systematic search protocol
- To formulate a well-focused clinical question
- To retrieve a higher % of relevant citations

PICO (TT) framework;

- Patient/Population (who/what)
- Intervention (diagnostic test/
treatment/prognostic factor)
- Comparison (what is the main alternative)

, - Outcome (what are you trying to accomplish/measure/improve/effect)
- (T)ype of question (therapy/diagnosis)
- (T)ype of study (the design that is best for the question)

Example: Does psychodynamic therapy (I) help depressed individuals (P) experience reductions in
depression on the Hamilton depression scale (a clinician-administered measure) (O), that are at least
as strong as those of cognitive behavioral therapy (C)?

Evidence: operationalization

- Summary scores for RCT are helpful, but also ask…
 Effect size: moderate = a few patients with large changes? many patients with smaller
changes?
 Percent improved: of completers or all who entered?
 Percent recovered
 Sustained efficacy: what timeline was used

Control groups and what it means to say “treatment ‘x’ works”

- Types of control
 No treatment
 Wait-list
 Treatment as usual (TAU) (=very often
substandard care)
 Active control
- No treatment, wait-list, TAU
 Control for passage of time
 Do NOT control for common factors
(therapeutic alliance)
 Do NOT control for expectation/placebo

RCT methods

- Unlike pharmacological RCTs, double-blinding is difficult
 Depressed patient enrolled in a study is likely to know whether s/he is receiving the real
treatment (expectancy, placebo, hope)
 Active control: expectancy very rarely assessed
 Intervention provider is likely to know whether s/he is providing the real treatment

Confirmation bias= tendency to favor information that confirms our theory (beliefs, hypotheses).

Researcher allegiance= the researcher’s ‘belief in the superiority of a treatment and in the superior
validity of the theory of change that is associated with the treatment’.



Lecture 2: Synthesizing evidence: meta-analysis
Today’s topics:

1. Methods and importance of systematic reviews and meta-analyses
2. Publication bias

Systematic review and meta-analyses;

, - Collate all evidence that fits pre-specified eligibility criteria in order to answer research
question
- Minimize bias using explicit, systematic methods
- Meta-analysis= use of statistical methods to summarize the results
- Different from a traditional narrative review;
 No systematically collected evidence
 (possibly) not objective
 No statistical summary of association

Systematic reviews are less biased than a normal review.

A disadvantage of a systematic review is that it takes a lot of time.

Two systematic reviews can have the same subject but very different conclusions due to;

- Other search terms
- Different inclusion and exclusion criteria

Why systematic reviews;

- Many studies, different results
- Overview
- Small effects
- Subgroup
- Reporting bias

Users of systematic reviews;

- Researchers
- Policy advisors guidelines
- Clinicians

Guidelines systematic reviews:

- Cochrane/Campbell
- PRISMA

Steps;

- Step 1: Research questions (PICO)
- Step 2-4: Searching (come up with search terms, searching for research)
- Step 5: Selecting studies
- Step 6: Collecting data
- Step 7: Assessing risk of bias
- Step 8: Analyzing data and meta-analysis
- Step 9: Reporting bias

Quality assessment (risk of bias); look at the individual studies included to assess the quality of the
studies.

Define research question with PICO

- Population
- Intervention/influence
- Control group/comparison