Some trials have excellent external validity, but many do not, particularly some of those performed by the pharmaceutical industry. Yet researchers, funding agencies, ethics committees, medical journals, and governmental regulators all neglect proper consideration of external validity. Judgment is left to clinicians, but reporting of the determinants of external validity in trial publications, and particularly in secondary reports and clinical guidelines, is rarely adequate and much relevant information is never published. RCTs cannot be expected to produce results that are directly relevant to all patients and all settings, but to be externally valid they should at least be designed and reported in a way that allows clinicians to judge to whom they can reasonably be applied.
No comments:
Post a Comment