Just days after an announced crackdown on researchers who fail to disclose their ties to drug makers, the editor of the Journal of the American Medical Association (JAMA) said she has been misled again, this time by the authors of a study linking severe migraines to heart attacks in women. All six of the study’s authors have done consulting work or received research financing from makers of treatments for migraines or heart-related problems but did not report their financial ties because they did not believe they were relevant to the study. Their research appears in JAMA’s latest edition. JAMA editor Catherine DeAngelis told the Associated Press she would have published the authors’ associations with drug makers had she known about them. JAMA on Tuesday posted a letter on its Web site explaining the omissions, DeAngelis’ response and issuing a correction. Last week, JAMA disclosed that authors of a depression study appearing in its pages failed to reveal ties to makers of antidepressants. Two months ago, JAMA reported similar omissions from authors of a study linking certain arthritis drugs to cancer.