'Efficacy and safety of imiquimod 5% cream for basal cell carcinoma: a meta-analysis of randomized controlled trial': a critical appraisal.

The main concerns related to the article by Jia and He are that the research question is replicative, it makes little sense to combine all BCC types in a meta-analysis, and it also makes no sense to combine an active treatment against a combination of vehicle and other active treatments. There are also concerns about bias related to the use of the same study data more than once in a meta-analysis. Furthermore, we have identified an example of covert duplicate publication, which further compounds the profusion of misleading systematic reviews.