"Given that publications report a wide range of values from analyses (e.g., means and standard deviations, r, F, t values, eta squared, partial eta squared, etc.), it can be extremely difficult to compute effect sizes that take each of these factors into consideration. This can make the process of a metaanalysis more time consuming that it necessarily has to be. I found one useful and time‐saving aspect of Comprehensive Meta‐Analysis is that it allowed me to enter effect size data from articles in a number of formats. Upon running the analysis, the programme would compute standardised effect sizes for each study (even though I might have used around 10 different types of data entry), as well as an overall effect size. Furthermore, even though I had over 50 moderators to assess, CMA made it simple to test each moderator, whilst offering the option to test moderators according to other specific study characteristics. This meant I could delve deeper into my data to see what was really going on. For these more sophisticated methods, the programme also reports the information required to compute additional statistics, such as tau squared within and between studies (enabling me to compute the R squared statistic), which are not provided by some other programmes but are commonly reported in published meta‐analyses."

Natalie Taylor, PhD - Researcher, Health and Social Psychology Group, Institute of Psychological Sciences, University of Leeds, Leeds

"We had no knowledge on meta‐analyses and were somewhat confused by the number of programs available. Most of them were not easy to use, not insightful and required a priori knowledge of metaanalyses statistics. There was one exception: Comprehensive Meta‐analysis. We downloaded the software and went through the easy‐to‐use tutorial. Within an hour we were performing our own metaanalysis! Our analysis was verified by our statistical department with excellent results, giving us further confidence to continue our analysis and resulting in an excellent paper in the top journal on pain research: Niesters et al., Do Sex Differences Exist in Opioid Analgesia? A Systematic Review and Meta‐ Analysis of Human Experimental and Clinical Studies. Pain, 2010, in press, doi:10.1016/j.pain.2010.06.012."

Albert Dahan, MD, PhD & Marieke Niesters, MD, MSc - Department of Anesthesiology, Leiden University Medical Center, Leiden, The Netherlands