Updating diagnostic test accuracy systematic reviews: Which, when, and how should they be updated?

Updating diagnostic test accuracy (DTA) systematic reviews (SRs) is fundamental in order to avoid making clinical decisions based on out-of-date and/or incomplete information. The decision of which SR to update should be based on the quality of the SR and on the currency of its topic. If SRs are considered worthy of updating, priority should first be established depending on the availability of elements of novelty (in terms of published studies, methodology, decisional approach, or standards of quality), as well as on the expected impact and value of information. Before starting the updating process, a careful work plan is necessary, refreshing the state of the art, the aim, and the methods. Once the update has been performed, new findings and conclusions should be clearly displayed.