Risiko for bias ved blindet versus ublindet vurdering af artikler i systematiske oversigtsartikler--en gennemgang af et Cochranereview

A Cochrane review investigated the effect of blinding information of authors, institutions, journals and sponsorships in assessing the presence of bias in trials that were assessed for inclusion in a systematic review. Six randomized trials were included. The results of these were quite heterogeneous and from this review it is not possible to conclude anything about the effect of blinding with certainty. However, it proved time-consuming to implement a secure blinding and until further evidence appears, it is recommended to refrain from attempts to do so.