“Its strength was that she included measures of both psychiatric mood diagnoses and personality disorders, and so was able to compare the long-term effects of both,” said E. Jane Costello, a professor of psychiatry and behavioral sciences at Duke University. (Dr. Costello’s long-term Great Smoky Mountains Study, in rural North Carolina, has similarly tracked mental disorders over a lifetime.)
“And she was statistically very good,” Dr. Costello said, which added rigor to the results.
Dr. Ezra Susser, a professor of epidemiology and psychiatry at Columbia, said of Dr. Cohen’s work: “Hers was a foundational study, in what we nowadays call life-course psychiatric epidemiology.”
Life-course studies like Dr. Cohen’s and Dr. Costello’s are especially crucial in psychiatry as a check on faddish diagnoses, Dr. Susser said. In the early 2000s, for example, doctors at Massachusetts General Hospital and elsewhere began diagnosing bipolar disorder in children as young as 3.
But studies like Dr. Cohen’s and Dr. Costello’s showed that the trend was mistaken. In adults, the disorder involves periods of sadness alternating with periods of mania. Young children, however, did not exhibit classic manias, the studies found, and those who were given the diagnosis so early rarely, if ever, went on to develop full-blown adult bipolar disorder.
Patricia Ruth Childs was born on Oct. 20, 1936, in Park Rapids, in northern Minnesota, the second of five daughters of John Keble Childs, a forester, and Margaret Richardson Childs, a teacher. She grew up in the nearby city of Bemidji.
After graduating from high school, she attended Hamline University in St. Paul and finished with a degree in English and music in 1958. She earned a Ph.D. in psychology at New York University, where she met Jacob Cohen, one of her professors and an authority on statistical analyses in the behavioral sciences. They married in 1969. Her first marriage, to Haider Walty, had ended in divorce.
Jacob Cohen died in 1998. She is survived by Ms. Bourne, from her first marriage; a son, Gideon Cohen, from her marriage to Dr. Cohen; two stepdaughters, Aviva Must and Marcia Cohen; seven grandchildren; three great-grandchildren; and her four sisters, Peggy Barker, Susan Brustman, Nancy Drews and Kathy Gordon.
Dr. Cohen was a researcher in the New York State Office of Mental Health in the 1970s when she and her husband published “Applied Multiple Regression/ Correlation Analysis for the Behavioral Sciences” — a landmark text in the field that, in defiance of its title, many students remember fondly.
