There are quite a few problems with the interpretation of this cohort. Most importantly, there is potential bias by indication. For example, women who needed more acetaminophen might have had conditions that could cause the outcome, rather than the acetaminophen. In addition, the doses were not known and more than 20,000 cases were excluded for missing interviews. Therefore, it is possible that they had many more parents with ADHD, which is often a genetic condition. The acetaminophen users had more muscle and joint diseases, more infections, and more psychiatric disease-which can affect the results, independent of acetaminophen.
Dr. Gideon Koren is director of the Motherisk Program at the Hospital for Sick Children, Toronto, and professor of pediatrics, pharmacology, pharmacy, and medical genetics, at the University of Toronto. He has no relevant disclosures.
FROM JAMA
The study was supported by the Danish Medical Council. Neither the researchers nor the editorialists had relevant financial conflicts to disclose.
