Evaluation of clinical trials of immunomodulators for prevention of recurrent respiratory infections in children.

Despite numerous clinical studies showing "significant differences" in favour of immunomodulators versus placebo in the treatment and/or prevention of recurrent respiratory tract infections, the efficiency of such treatments is still not readily acknowledged by a large part of the medical profession nor by governmental authorities in several countries. In an effort to analyze the causes of this scepticism we performed a retrospective study of 15 clinical trials, using a series of quality assessment criteria. From the results of our analysis we propose a series of recommendations for improving the quality of clinical trials with immunomodulators. Furthermore, in order to avoid suspicion of a publication bias, we recommend setting up a registry of all ongoing clinical studies with immunomodulators.