To the Editor: I read with great interest the article by Sidney Zisook, M.D., and colleagues (1) on their study of depressive symptoms in a clinically stable group of outpatients with schizophrenia who were aged 45–79. They concluded (p. 1741) that their findings confirmed those of Cohen (2). In the introductory section of the article (p. 1736), Dr. Zisook and colleagues cited Cohen’s article, saying that it was on a study of "schizophrenic patients aged 55 and older" in whom "high scores on a depression rating scale were associated with positive symptoms, physical limitations interfering with activities, diminished social networks, and lower income."

However, when I located Cohen’s article, I found that it was not a report on a specific study, but a relatively general article on selected aspects (issues in research, psychopathology and social functioning, and treatment outcome) of aging persons with schizophrenia. This must be an error. Since I should not be the only person interested in the earlier study that Dr. Zisook and his colleagues had in mind, I would be much obliged if they could inform all readers of the accurate reference.