Marko Curkovic in his letter (2017) points out that using Google Search in our systematic review (Piasecki et al. 2017) could have led to the so-called “bubble effect”, a form of selection bias. We take seriously this concern. Google Search is indeed an imperfect tool to perform systematic reviews: the search algorithm is not known and cannot be controlled, Google adapts the search to each user...

background recently there has been a significant increase in the number of systematic reviews addressing questions of prevalence. key features of a systematic review include the creation of an a priori protocol, clear inclusion criteria, a structured and systematic search process, critical appraisal of studies, and a formal process of data extraction followed by methods to synthesize, or combin...

BACKGROUND Systematic reviews provide a synthesis of evidence for practitioners, for clinical practice guideline developers, and for those designing and justifying primary research. Having an up-to-date and comprehensive review is therefore important. Our main objective was to determine the recency of systematic reviews at the time of their publication, as measured by the time from last search ...