Munn, Z.Pollock, D.Barker, T.H.Stone, J.Stern, C.Aromataris, E.Schünemann, H.J.Clyne, B.Khalil, H.Mustafa, R.A.Godfrey, C.Booth, A.Tricco, A.C.Pearson, A.2023-06-062023-06-062023BMJ Evidence-Based Medicine, 2023; 28(3):148-1502515-446X2515-4478https://hdl.handle.net/2440/138663Have we, as an evidence-based health community, opened the Pandora's box of evidence synthesis? There now exists a plethora of overlapping evidence synthesis approaches and duplicate, redundant and poor-quality reviews.1-4 After years of advocating for the need for systematic reviews of the evidence, there is a risk that this message been disseminated too widely and has been misinterpreted in this process. We have reached a point where in some fields more reviews exist than clinical trials, where same topic reviews are being conducted in parallel, and evidence syntheses possess limited utility for decision-making because of their poor quality or poor reporting.To paraphrase the late Douglas Altman,5 it is possible we are now at a stage where we need less reviews, better reviews and reviews done for the right reason - as opposed to the current state of mass production (approximately 80 reviews per day)6.en© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. Open access This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/.Evidence-Based PracticeSystematic Reviews as TopicHumansEthics, MedicalJournal article10.1136/bmjebm-2022-1120652023-06-06625001Munn, Z. [0000-0002-7091-5842]Pollock, D. [0000-0002-6604-0609]Barker, T.H. [0000-0002-6897-814X]Stone, J. [0000-0002-3787-6175] [0000-0002-7848-1401]Stern, C. [0000-0002-0924-5042]Aromataris, E. [0000-0001-7238-5833]