26. What if you're missing a standard deviation and only a similar summary statistic is given?
Data extraction tips for meta-analysis - tip 26
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.
Follow updates on this blog and related news, and to find out about other examples of statistics being made more broadly accessible on Twitter @dataextips