Anita Kaplan Bahn (1919/1920 – July 19, 1980) was an American epidemiologist, biostatistician, and cancer researcher.^[1][2]

Bahn was originally from New York City.^[1] She left high school at the age of 15, and earned a bachelor's degree in biology four years later from Hunter College, together with a certification allowing her to teach high school biology. She would also go on to study "physics at New York City College; botany and bacteriology at Cornell University; mathematics and statistics at American University and at George Washington University", but without completing those programs to a graduate degree.^[2]

She became head of outpatient studies at the National Institute of Mental Health from 1951 to 1966.^[1][2] During this time, she earned a Sc.D. from Johns Hopkins University in 1960. Her dissertation, supervised by Jerome Cornfield, was A Methodological Study of the Outpatient Psychiatric Clinic Population of Maryland, 1948-59.^[3] She then returned to academia as an associate professor of biostatistics at the Medical College of Pennsylvania. While there, she worked towards an M.D., which she earned in 1972.^[1][2]

She became chief epidemiologist of Maryland for the following two years,^[1][2] and then became a professor of community medicine and epidemiology at the School of Medicine at the University of Pennsylvania.^[1] At Pennsylvania, she helped found a graduate program in epidemiology, and led a research center on the epidemiology of cancer. She was also affiliated with the Fox Chase Cancer Center and held an adjunct position at Temple University.^[2]

In 1980, she was recruited to head a new epidemiology program in the Graduate School of Public Health at San Diego State University,^[4] but she died at age 60 of a cerebral hemorrhage at the University of Pennsylvania hospital before she could take up her new position.^[2][1]

Bahn authored Basic Medical Statistics (Grune & Stratton, 1972).^[5] and, with Judith S. Mausner, she co-wrote Epidemiology: An Introductory Text (Saunders, 1974).^[6]

Bahn was named a Fellow of the American Statistical Association in 1970.^[7] She was also a fellow of the American Public Health Association and the American College of Preventive Medicine.^[2]

Her husband, Ralph Bahn, with whom she had two children, died in the early 1970s;^[1] she married again, in 1980, the year of her death, to nuclear physicist and science fiction fan Milton A. Rothman.^[1][2]