Meta-analysis procedures Flashcards
(20 cards)
What should be tabulated for study characteristics in a meta-analysis?
Study characteristics related to review of PICO terms
What is the preferred effect measure for dichotomous outcomes?
RR (Relative Risk)
avoid using risk difference for individual studies (due to lack of consistency)
What effect measures are used for continuous outcomes?
Mean difference or standardized mean difference
What transformation may be needed for data analysis in meta-analysis?
Log transformation
What are the two main analysis methods in meta-analysis?
Fixed effects and random effects
What does fixed effects assume about variability in intervention effects?
Variability is the same in every study
What does random effects assume about variability in intervention effects?
Variability is not the same across studies
How is the result of random effects viewed in meta-analysis?
As the average intervention effect
What does the random effects model represent in terms of intervention effects?
Our lack of knowledge about why real or apparent intervention effects differ
Why is random effects preferred over fixed effects?
It incorporates the assumption that different studies estimate different, yet related, intervention effects
What happens to confidence intervals (CIs) in random effects when heterogeneity is present?
They are larger
Which method is used for random effects meta-analysis in RevMan?
DerSimonian and Laird method
When will random and fixed effects models give identical results?
When there is no heterogeneity among the studies
How is the result of fixed effects viewed in meta-analysis?
As a typical intervention effect
When should fixed effects be used in meta-analysis?
If only 2 studies, one large good study with lots of lower-quality small studies, or minimal variability between studies
Which methods are preferred over inverse variance methods in fixed effects?
Mantel-Haenszel methods
What is heterogeneity in the context of meta-analysis?
Presence and extent of variability between studies
Heterogeneity can impact the interpretation of results.
How should statistical heterogeneity be considered?
It should be taken into account when interpreting the results
Statistical heterogeneity may indicate varying study outcomes.
What methods can be used to explore sources of heterogeneity?
Subgroup and sensitivity analyses
These analyses help understand the reasons for variability.
What is the importance of following the subgroup analysis plan?
To avoid undue emphasis on particular findings
Adhering to the protocol ensures objectivity.
