Meta-analyses of clinical trials: are we getting lemonade from lemons?

Meta-analyses guide planning of clinical trials and clinical care, but are subject to all the methodologic problems and potential biases present in the underlying trials. Furthermore, publication bias often contributes to overestimated benefit in meta-analyses of small trials, which are often 'corrected' by subsequent large trials. Meta-analyses are no substitute for large robust trials.

Automated summary

Meta-analyses are important for guiding clinical trials and care, but they can be affected by methodologic problems and biases in the underlying trials. Publication bias often leads to overestimation of benefits in small trials, but this can be corrected by subsequent large trials. It is essential to conduct large, robust trials as they are irreplaceable by meta-analyses.