What are systematic reviews
They systematically evaluate and summarise current knowledge.
A review of a clearly formulated question that uses systematic and 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 analyses may or may. It be used to summarise and analyse the results of the studies.
Statistically pooling of study findings aka meta analysis
Brings together all the high quality evidence on a research question.
Highlight the gaps in the evidence, end confusion about the benefits and harms, dispel myths, yield new insights, reduce of any flaws or errors in a single study, tells us when enough research has been done to confidently reach a conclusion, can identify where publication bias is present.
Grey literature is academic term for unpublished data,literature, for army does a lot of work in research and they don’t publish it.
Conclusions can be misleading because you can’t control the data so if they messed up with data then your conclusions will be bad.
Most of the time the answer is that there is not enough good quality evidence..
Stages of systematic review:
Define your research question
Write and agree a protocol (and publish it)
Conduct a systematic search of the literature
Screen the literature for eligibility
Extract relevant data from the included studies
Assess the quality of included studies
Synthesise the findings of the included studies
Write up (and publish)
Systematic reviews journal and you can publish your protocol there.
Define your research question:
Topic ➡️ narrower ➡️ focus ➡️ research question
American civil war ➡️ battle of Gettysburg ➡️ residence ➡️
Where to start
What databases will you use? Typically a minimum of 3.
Will you look for grey literature and if so how?
What search terms will you use and how will you combine them?
Will you use filters to exclude certain types of articles?
How will you manage your health results?
Tips for designing a search strategy:
Involve a librarian or someone with experience
Look at search strategies from other similar systematic reviews and borrow
Before committing to anything, test the search yourself from your proposed databases
Maximise your search – triangulate:
Contact experts in the area
Reference lists of relevant articles
Google scholar citations of key articles – forward citation tracking aka click on cited by x number link on google.
A flow diagram should be in all systematic reviews
Patient, population or problem
Intervention, exposure, prognostic factor
Comparison or intervention (if appropriate)
Outcome you would like to measure or achieve
What type of question are you asking?
Type of study you want to find
Consider what types of study will you include,
Consider what types of participants
What types of outcome measures will you include
How many people will screen the titles and abstracts, and the full text
Now you need to systematically collect all the relevant data:
General information e.g. Author, year, funder
Methods e.g. Study designs
This is typically a table
Assess the quality of included studies
Decide on a criteria for what a good quality study would look like
Rate the quality of included studies as low, medium,or high risk of bias -every study will have a limitation. Here you could do a sensitivity study.
Informs the confidence you state in the findings of the studies/systematic reviews
In my apps is a Cochran review manager. Read the handbook
It has to be a result section taking into account the quality of the evidence.
This can be done in a number of ways:
Meta analysis qualitative synthesis
Combines the results from 2 or more studies
Estimates an average or common effect
Optional part of SR, not always possible
Why to do one:
Quantity treatment effects and their uncertainty
Explore differences between studies
Settle controversies from conflicting studies
Generate new hypotheses
Standard deviation is the variability
In the forest plot diagram if anything crosses the line, there is no effect. I am 95% sure of…. there is no difference or there is difference.
The point estimate is minus…. so I am 95% confident that they successfully did what they wanted to do.
Managing the SR process:
Include someone with SR experience
Tends to generate a lot of information and there is a lot to manage and record.
Need to think through carefully how this will be managed
Can do it all on paper but there is free software e.g. Review manager that you can use.
Consider how do we prioritise outcomes?
When do you reach the point of comparing apples and oranges? To what extent should data from studies be pooled together?
The Joanna Briggs institute healthcare and public health
University has a diploma with Cochran reviews.[Top]