Doing a Systematic Review: A Student's Guide
Second Edition
Chapter 8. Understanding and Synthesizing Numerical Data from Intervention Studies
Creative visuals and engaging audios are a great way to reconsolidate your knowledge! Check out the suggested online presentations and podcasts below.
Further information on heterogeneity/subgroup analysis
http://training.cochrane.org/resource/exploring-heterogeneity
Podcast on the risks of using multiple analyses in clinical trials/systematic reviews
http://training.cochrane.org/resource/mulitiplicity-and-subgroup-analysis-beware