Born to parents who espoused that all children – regardless of gender - be trained to support themselves, Barringer earned her MD from Cornell University Medical School in 1901- a time when few women trained as physicians. Upon graduation, she took the qualifying exam for an internship position at Gouverneur Hospital of New York. Despite receiving the second highest grade, her application was denied because of her gender. Reapplying one year later, and supported by lobbying from political and religious figures, she was accepted, becoming the first woman physician to receive post-graduate surgical training in hospital service, and the first female ambulance surgeon.

Mother of three children and married to a physician, Barringer's professional concerns included medical education for women, public health, women's suffrage, and reforms for the treatment of incarcerated females. A member of numerous professional associations, she served as the President of the American Medical Women's Association in 1942. As Chairman of the Special Committee of the American Medical Women's Association, Dr. Barringer was decorated by the King of Serbia for championing the service of female physicians during WW I. As Co-chair of the War Service Committee, she organized the American Women's Hospital in Europe, which provided medical and surgical care during the war and post-war reconstruction.

Her autobiography Bowery to Bellevue: The Story of New York's First Woman Ambulance Surgeon was made into the MGM 1950 film The Girl in White . Dr. Barringer also contributed extensively to medical publications.