Comparison of basic methods in clinical studies and in vitro tissue and cell culture studies reported in three anaesthesia journals.

Tissue and cell culture (in vitro) studies reported in the 1997 issues of the British Journal of Anaesthesia, Anesthesia and Analgesia, and Anesthesiology were compared with groups of clinical studies selected at random from the same issues. Comparisons were of some basic aspects of study design and reporting that might lead to bias. The aspects examined were sample size, randomization and reporting of exclusions and withdrawals. Two groups of 53 articles were compared: sample size was smaller in in vitro than in clinical studies (median 6 vs 19); randomization was reported in five in vitro studies and in 37 studies; and failures were reported in two in vitro studies and in 43 clinical studies. This hinders interpretation of reported tissue and cell culture studies. Where possible, tissue and cell culture studies should be conducted, reported and assessed for publication to standards equivalent to those for clinical studies.