Report by former Motherisk lab director of cocaine exposure in a child is subjected to an expression of concern

Gideon Koren

A pediatrics journal has issued an expression of concern for a 2007 paper by a group of Canadian researchers whose leader, Gideon Koren, resigned in 2015 under a cloud after concerns surfaced about the integrity of the data in hundreds of his published studies. 

Koren, once a prominent pediatrician and pharmacologist at the University of Toronto’s Hospital for Sick Children, ran the institution’s Motherisk Drug Testing Laboratory, which conducted hair testing for perinatal exposure to drugs and alcohol. In 2015, an investigation prompted by The Toronto Star found serious problems with the tests, which had been used in “used in thousands of child protection cases and several criminal cases.” 

Koren stepped down that year, and in 2019 relinquished his license to practice medicine in Ontario. Reporting by the Star prompted Koren’s institution to order a review of more than 400 of his published papers. To date, by our count, journals have retracted five of Koren’s papers, corrected four, and have now issued three expressions of concern. 

The newly flagged article, “Chronic cocaine exposure in a toddler revealed by hair test,” appeared in Clinical Pediatrics in 2007. Here’s the notice

In late 2018 and 2019 the University of Toronto, SickKids/Motherisk (the “Hospital”) notified the publisher and then editor that authors Dr. Michelle Shouldice and Dr .Marcellina Mian did not consent to this Case Report being submitted for publication and have asked to be removed as authors on this article. Additionally, the Hospital reported that the Motherisk Drug Testing Laboratory (MDTL), founded and directed by Dr. Gideon Koren, was closed in 2015 after an independent review of the lab’s activities was conducted and it was concluded that the MDTL hair-strand drug testing used by the lab was inadequate and unreliable for use in forensic proceedings. The Hospital stated that the testing referenced in this article is flawed and did not use accepted standards. Dr. Koren strongly disputes these claims.

It should be noted that any real or perceived conflict of interest that Dr. Koren had with MDTL were unknown/undivulged at the time of publication of this article.

Given the above concerns that are material to the article’s findings, the Editor and Publisher are issuing this expression of concern.

The paper has been cited nine times, according to Clarivate Analytics’ Web of Science.

The testing scandal isn’t Koren’s only brush with misconduct allegations — or with authors who claim that he misrepresented their involvement in papers. In 2019, as we reported, Therapeutic Drug Monitoring retracted a 1999 article by Koren after learning that he had published the paper without the consent of co-author Nancy Olivieri. According to The Star:

In 2000, the heads of Sick Kids and U of T suspended and fined Koren, who was also stripped of an endowed chair for “repeatedly lying” and sending anonymous “poison pen letters” to doctors and the media disparaging Olivieri and her supporters. He denied writing the letters until DNA evidence provided irrefutable proof.

After leaving Toronto Koren moved to Israel, where in 2018 his new employer, the Maccabi healthcare fund, launched an investigation into his conduct. 

Koren was most recently at the Dr. Miriam and Sheldon Adelson Medical School at Ariel University. He did not immediately respond to a request for comment.

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