Systematic reviews

Question 1

What is a systematic review?

Answer 1

Type of literature review that uses systematic methods to collect secondary data.
Allows critical appraisal of past studies to bring together BODY information into more concise reading - widespread view of information.

Question 2

Why do you need to conduct a systematic review prior to conducting your own study?

Answer 2

Answer may already be out there - review current information before starting another trial.

Question 3

What are the functions of systematic reviews?

SIIPER

Answer 3

Save readers time
Provide reliable evidence
Resolve inconsistencies
Identify gaps of research
Identify when questions have already been fully answered
Explore differences between studies

Question 4

What types of studies show strongest to weakest evidence?

Answer 4

Strongest at the top

Systematic review
Intervention study e.g. RCT
Observational study
Lab study

Question 5

How can you ensure a well-formulated study for a systematic review, and break down the steps?

Answer 5

PICO question format
Participants - who is the review interested in studying

Interventions (exposure) - what is the intervention or group of interventions of interest

Comparisons - what will the interventions be compared to?

Outcomes - which outcomes will tell you which intervention is most effective

Question 6

What tools can we use to assess how well a systematic review has been carried out?

Answer 6

AMSTAR2
ROBIS

Question 7

What oral health group organisation can be used to look at systematic reviews?

Answer 7

Cochrane oral health

Question 8

What tools can be used in the assessment of papers as part of a systematic review?

Answer 8

Quality assessment tools
- Composite scales
- Component approach

Question 9

What are 4 different types of reporting biases for statistically “positive” results?

Answer 9

Publication bias
Time-lag bias
Language bias
Citation bias

Question 10

What is publication bias?

Answer 10

If there is a positive statistical significance between the two groups (e.g. powered and manual toothbrush) the study is more likely to be published

Question 11

What is time lag bias?

Answer 11

When a study is more likely to be published more quickly if the results are more exciting - positive effect more likely to be published than null effect

Question 12

What are the components of risk of bias assessment for trials (RCT)?

SABIS

Answer 12

Sequence generation
Allocation concealment
Blinding
Incomplete outcome data
Selective outcome reporting

Question 13

What is meta-analysis?

Answer 13

Optional part of a systematic review - can have MA without SR but uncommon
Uses statistical methods to calculate a treatment effect based on pooled data from a group of studies - aim to identify overall trend of results.

Question 14

When should a meta-analysis be undertaken?

Answer 14

When there are minimal differences in characteristics across studies
Same outcome measure
Data in each study are available

Question 15

What does a forest plot do?

Answer 15

Displays information graphically from a meta-analysis.

Question 16

What are 5 factors that can lower quality of body of evidence from a meta-analysis?

Answer 16

High or unclear risk of bias
Inconsistency between studies
Indirectness
Imprecision
Publication bias

Question 17

What is the definition of confidence interval?

Answer 17

Calculated for a measure of treatment effect (for example a risk ratio).
Shows the range within which the true treatment effect is likely to lie.

Question 18

What is the risk ratio/ relative risk?

Answer 18

Risk relative to a control/ intervention group.
What is the increase in the risk of outcome from the control vs. intervention group?
Where RR = 1 - there is no difference between intervention and control.