L4 07/02 Flashcards
Why review evidence?
For EBP we need to work through the available evidence to find the reliable and relevant sources and discard the others
What challenges are there?
- Information overload
- High-quality, poor-quality internet sources
- Publication biases
- Variable research quality
- Conflicting or inconclusive results
- No relevant evidence available
What are the four classes of literature review as review methods?
- Narrative reviews of evidence
- Systematic reviews
- Meta-analyses of evidence
- Meta-synthesis
What is a narrative/traditional review used for?
- To support ongoing work
- Critiques and summarizes a body of literature
- Draws conclusions about a topic
- Identifies gaps or inconsistencies in a body of knowledge
Give 3 weaknesses of narrative/traditional review
- Requires a sufficiently focussed research question
- A large number of studies may make it difficult to draw conclusions
- The process is subject to bias that supports the researcher’s own work
Give 2 features of narrative/traditional review
- Useful approach to critically engage with the wider evidence base so as to address a clinical or practice issue
- Methodologically rigorous, and uses a systematic approach, but is NOT the same as a systematic review
Give 3 limitations of narrative/traditional review
- Cannot be used to evaluate the effectiveness of interventions as not all available evidence is used
- Does not attempt to collate the statistics of included evidence or to apply new statistical tests as no statistical analysis
- Reporting the narrative review must show transparency of process and method but in many cases isn’t present
Narrative/traditional review stages
- Clarify the ‘problem’ to be addressed
- Articulate a clear review question
- Specify the aims of review
- Specify inclusion and exclusion criteria
- Describe & justify search parameters and sources
- Apply a rigorous process and justify all decisions taken
- Identify and retrieve relevant evidence
- Appraise research quality to justify inclusion
- Extract relevant data/findings
- Summarise key findings (results table)
- Interpret the evidence in relation to the question
What is a systematic review used for?
- Aims to answer a specific research question related to the effectiveness of an intervention
- Gathers ALL relevant data (published & unpublished e.g., preliminary findings)
- Uses clear and repeatable methods
Give 5 features of systematic review
- Transparent methodological process
- Aims to maximise the validity and reliability of review conclusions
- Designed primarily to address questions of the effectiveness of healthcare interventions
- Systematic reviews are driven by rigorous protocols
- Method normally involves further statistical analysis of data – compared all of the outcome’s form all of the published studies
Outline the systematic review method
- Protocol driven
- All systematic reviews MUST aim to address a specific research question related to the effectiveness of healthcare interventions
- Specify the PICOS: Participants, Intervention, Comparison, Outcomes, Studies
Narrative vs systematic
Broad scope - focussed
Not usually specified - comprehensive & explicit
Variable - rigourous
Qualitative summary - quantitative summary
Sometimes evidence based - usually evidence based
What is a meta-analysis?
- A form of systematic review but with statistical analysis of quantitative studies
What does a meta-analysis involve?
- Formally integrates findings from a large number of studies to enhance understanding.
- Essentially takes findings from several studies on the same subject, combines their data and analyses them using statistical procedures to draw conclusions and detect patterns and relationships.
What is a meta-synthesis?
- The qualitative version of a meta-analysis; this uses non-statistical techniques such as integration, evaluation and interpretation to identify common themes.
