Review Articles Flashcards
What is a review of literature?
A body of text that aims to review:
- the critical points of current knowledge and or
- methodological approaches on a particular topic.
There are two types- standard and systematic reviews.
What is a standard review?
Examine results of small part of research evidence, and take claims of authors at face value
Although they are often conducted by ‘experts’, who may have a thorough knowledge of the research field, they are disadvantaged in that the authors may have pre-conceived notions or biases, and may overestimate the value of some studies
What is a systematic review?
A review of a clearly formulated question that uses systematic and explicit methods to identify, select, and critically appraise relevant research, and to collect and analyse data from the studies that are included in the review. Statistical methods (meta-analysis) may or may not be used to analyse and summarise the results of the included studies.
What is the difference between systematic and standard reviews?
Systematic reviews are much better, in that they provide:
- high-quality
- relevant,
- accessible,
- up-to-date information
for health decision makers to access. Along with meta-analyses, they provide the best evidence available within the hierarchy of scientific evidence.
This contrasts to standard reviews, which often have bias associated with them, including author, selection and publication bias. They also do not have a hypothesis stated, and also findings cannot be reproduced independently as conclusions may be subjective.
How is a systematic review conducted? (6)
Question- Focused question using PICO format
Search- Electronic and hand, no language restriction
Appraise- Assess quality, exclusion/inclusion criteria, and have more than one reviewer
Extract- Data extraction tools, use of sheet and defined criteria on what to be included
Analyse- Data pooled from all studies, and meta-analysis if appropriate
Present- Presentation of results narrative or graphically with forest plots
WHAT IS META-ANALYSIS?
The statistical combination of results from two or more separate studies
What are potential advantages of a meta-analysis?
• Improvement in precision
• Answer questions not posed by individual studies
• Settle controversies arising from apparently conflicting studies or generate new hypostheses
WHEN CAN YOU USE META-ANALYSIS?
• When more than one study has estimated an effect
• When there are no differences in study characteristics that are likely to affect outcome
• When outcome has been measured in similar ways
• When studies and results are homogeneous we use fixed effect models
• When studies and results have minor heterogeneity we use random effect models
• Too much heterogeneity NO meta analysis
WHAT MAKES A GOOD REVIEW?
Quality- of review and studies included in review
Finding as much information/studies as possible- electronic databases, hand-searching
Minimising bias- randomisation etc.
What are some disadvantages of systematic reviews?
• Rapid advancement of science - out of date quickly/updated frequently
• Lot more work - more time, expensive
What is Cochrane?
A Global network of health and social care practitioners, researchers, patient advocates and others, with a mission to promote evidence-informed decision making by producing high quality, relevant, accessible systematic reviews and other synthesized research evidence.
What is Cochrane’s purpose?
International not-for-profit organization, founded in 1993. Works collaboratively with health professionals, policy makers and international organizations, eg. WHO to support the development of evidence based guidelines and policy.
What are the principles of Cochrane? (10)
- Collaboration
- Building on enthusiasm of individuals
- Avoiding duplication of effort
- Minimizing bias
- Keeping up-to-date
- Striving for relevance
- Promoting access
- Ensuring quality
- Continuity
- Enabling wide participation
