The Publisher and Editor are issuing an Expression of Concern on the article titled “Chromium Supplementation and the Effects on Metabolic Status in Women with Polycystic Ovary Syndrome: A Randomized, Double-Blind, Placebo-Controlled Trial” [Ann Nutr Metab. 2015;67(1):42–48, DOI: 10.1159/000438465] by Mehri Jamilian and Zatollah Asemi.

Following publication, concerns were raised regarding the article by Jamilian and Asemi regarding discrepancies in sites between the trial registration and the article, possible undeclared conflict of interest with the study material provider and concerns about some of the data presented.

The concerns have been investigated by the National Committee for Ethics in Biomedical Research at the Iranian Ministry of Health and Medical Education. As our investigation is ongoing, we are issuing an Expression of Concern and readers should thus interpret the data presented in the article with caution. Appropriate editorial action will be taken once the investigation is concluded.