Systematic Review Flashcards
Systematic review and clinical practice guidelines are
pre appraised and summarized
Flaw though is that the reader must understand each of the formats
Systematic review is a
secondary analysis of original studies focusing on one element or evidence based question
What is the goal of a systematic review
to draw a conclusion based on the cumulative weight of the evidence on the element of interest
Where is a good place to look for systematic reviews
Cochrane Collaboration library
Types of reviews that can be found
Intervention benefits/harms Diagnostic test accuracy Prognostic outcomes Methodology Qualitative
Systematic reviews are research studies with their own
Designing elements:
Methods for identifying and selective studies to include
Review criteria to determine study quality
Processes for drawing conclusions from the body of evidence
Formal results section with qualitative and or statistical conclusions
- it is filtered info
Systematic reviews that use a quantitative method for drawing conclusions are called
Meta-analyses
- pool data from individual studies, creating larger sample size and inc power –> important to consider publication bias
- all studies in the review have to be similar in design
Heterogeneity
differences in methodology, populations, interventions, or study quality can affect whether studies should be combined
Evidence on systematic reviews should be assessed based on
design and execution that may have biased results
To avoid selection bias - review authors should
search all relevant electronic and print databases and collections
Inclusion and Exclusion criteria
Has to be determined in advance
typically includes study design criteria, language and publication
Results
summarizes the info induces descriptive info about the evidence: Research design Population Sample size Outcomes Interventions
Results - quantitative
likelihood ratio odds ratio effect size relative risk confidence inteval
The most useful way to determine statistical importance
confidence interval
Forest plots
presents a variety of info about studies combined in a met-analysis and presented overall result of the data combination
Forest Plot - line of no effect
direction and strength of results
Forest plot - squares
mean effect of individual study
Forest plot - diamond
mean effect of meta-analysis; represents the CI of the mean effect
Forest plot - chi square
test for heterogeneity
Sensitivity analysis
a way of evaluating whether findings would change if certain studies were removed from the analysis
When a statistical analysis is not possible then what
qualitative info is presented
Vote counting, or polling each author
If statistical importance cannot be demonstrated then
Study importance must be inferred from similar results in multiple studies
3 considerations when applying evidence from systematic reviews
- Appropriateness of element of interest to therapists setting and patients
- That the subjects in the reviews resemble the patient
- That the element of interest is compatible with patients preference and values
Clinical practice guidelines are
systematically developed statements to assist in decisions about appropriate health care for specific circumstances
Clinical practice guidelines intent is to
improve efficiency and effectiveness of health care and are based on current best evidence and expert judgment
Primary producer of CPG
AHRQ
GRADE - recommendations to implement a guideline “Strong For”
confident desirable consequences outweighs undesirable consequences
GRADE - recommendations to implement a guideline “Weak For”
Less confident desired consequence outweighs
GRADE - recommendations to implement a guideline “Weak against”
less confident undesired consequence outweighs desired
GRADE - recommendations to implement a guideline “strong against”
highly confident undesirable consequence outweighs desired outcomes
AGREE II
quantitative process for evaluating CPG
Does not address clinical validity of recommendations
Validity of CPG needs to be assessed on
Currency of the element of interest
New evidence refuting previous findings
Clinical or societal changes in outcomes or care
Changes in health care resources
Applicability of CPG is determined by
Factors related to condition of interest
Similarity to the patient in question
Other options available
Practice environment or setting
Summary - Systematic reviews do what
synthesize info from individual studies to arrive at a conclusion based on the weight of evidence
Summary - CPG are
statements to facilitate decision making and quality of care
CAT - is it unlikely that important, relevant studies were missed
Methods
CAT - were the criteria used to select articles for inclusion appropriate
Methods
CAT - were the included studies sufficiently valid for the type of question asked
Methods
CAT - were the results similar from study to study
Results