She performed research in the areas of autism spectrum disorders in children (formerly "childhood schizophrenia"), suicide and violence, and was one of the first researchers to suggest that mental disorders in children might have a neurological basis, rather than attributing them to the child's bad behavior or poor upbringing. Because she was not trained as a psychologist, but rather as a medical doctor and psychiatrist, most of her work focused on diagnosing mental disorders in children. She also served as the head of the children's psychiatric service at Bellevue Hospital for 21 years starting in 1934. In 1954, she testified at the Senate Subcommittee of Juvenile Delinquency hearings on the effects of crime and horror comic books as a medical expert for National Comics (now DC comics) with a job as an advisor for the company.