What if I’m missing a standard deviation and only another measure of dispersion is reported?
Data extraction tips for meta-analysis
Here's a tip...
You can derive estimates of standard deviations from other reported summary data, but be aware of the assumptions underlying your estimates.
Dr Kathy Taylor teaches data extraction in Meta-analysis. This is a short course that is also available as part of our MSc in Evidence-Based Health Care, MSc in EBHC Medical Statistics, and MSc in EBHC Systematic Reviews.
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