We continue to see an increasing number of SPR in Australia. Here is an article I wrote and published in the USA with Russ and Yaroslav (US based) http://www.jpands.org/vol21no4/ng.pdf
Another new editorial appeared this year entitled "Risk factors for Sham Peer Review" found in
This is an indirect way of answering your question: peer review has never been validated but casually used a tool for the perpetrator's desire.
This year, one of our ongoing research projects is to formally register a group to search the English speaking literature for studies on SPR in the Campbell Review and then formally present our findings. Those interested please discuss here.
We are particularly interested in commencing an SPR Subgroup with the Crime and Justice Group: https://www.campbellcollaboration.org/about-campbell/coordinating-groups.html
Those with Cochrane Skills are particularly welcome.
The Campbell Collaboration Crime and Justice group focuses on systematic reviews in criminology and criminal justice. We really ought to exploit this as the Managing Editor is Angela Higginson, QUT, QLD!
We hope to conduct formal systemic prospective review of English language studies world wide on Dr Russell Broadbent's original presentation in 2017 of the "Sham Peer Review - a Proposed Classification" found in https://www.hpara.org.au/copy-of-video-and-press
It has not been formally announced: we hope to present a poster (and others) on the numeric classification of Peer Review which will then direct readers to the proposed classification of SPR. We do not think we will be able to present at the Melbourne Meeting on Quality and Safety by the IHI-BMJ.