Recently, the work (Martins et al. 2018) “Evaluation of the efficiency of fluoride-releasing adhesives for preventing secondary caries in vitro: a systematic review and meta-analysis” was published in European Archives of Paediatric Dentistry, which examined the efficiency of fluoride-releasing adhesives for preventing secondary caries in vitro. But here we had a question on section of search strategy in this work. The authors reported that three electronic databases were searched, but their report on search strategy may be a mistake. We know that different databases have different index approaches, and there only PubMed database have this search format—“[MeSH Terms]” and “[Title/Abstract]”. However, the authors did not mention that this was a search strategy of PubMed. Therefore, this is not in compliance with (Moher et al. 2009) PRISMA guideline and may confuse new beginners.