Meta-Meta-Analysis

To add to the 'King Kong versus Godzilla' arguments about whether a single large randomised trial is better than a meta-analysis of smaller trials we now have to add problems of discrepancies of meta-analyses themselves. The study of the value of cholesterol lowering and the effects on coronary heart disease [1] is the first Bandolier has found which looks at the results of different meta-analyses and tries to prise out nuggets of philosophical gold.

Is cholesterol lowering beneficial?

Twenty-three separate meta-analyses were found. Outcomes examined were those of total mortality, cardiovascular mortality and nonfatal cardiovascular disease. As the Table shows, the results of the analyses overwhelmingly supported cholesterol lowering for reduction in nonfatal cardiovascular disease and cardiovascular mortality, but not total mortality.