Most systematic reviews that used the term 'update' in title/abstract were not an updated version

Objective: To analyse whether articles labelled as systematic reviews or meta-analyses (SRs/MAs) in the title and used updated or update in the title or abstract are indeed a report of an updated version of a previously existing SR/MA. Study design and setting: We searched PubMed for SRs/MAs, using descriptors updated/update in the title/abstract published in 2018-2019. We analysed how the articles used the term "update"/"updated" and whether the previous version of SR was referenced. We surveyed authors who indicated that the SR was an updated version, but there was no reference to the original SR. Results: Among 1118 included articles, most (N=716 ; 64%) used the term "update" only to denote that an SR includes recent data. Among 47 authors eligible for survey, 15 replied (32%). Six authors (40%) stated that their article was an updated version and gave reference to the previous version, while 9 authors (60%) stated that their SR was not an updated version of a previous SR. Conclusion: Most SRs that used the term "update" in title/abstract were not an updated version of an SR. Authors should use the descriptor "update"/"updated" in their title/abstract only to refer to a new version of an SR to avoid ambiguity. Keywords: meta-analysis ; nomenclature ; research methodology ; systematic review ; terminology ; update.