Neither the desired summary statistic, nor a similar statistic is reported
Data extraction tips for meta-analysis
Here's a tip...
You can use imputation to deal with missing sample sizes, means and SDs, using reported data or data from other studies.
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 Medical Statistics and MSc in 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