In early 1914, Winterbotham was appointed a captain in the militia of the
Australian (Army) Medical Corps. During
World War I, he provided services to training sites around
Brisbane. Following the war he was honorary surgeon at the
Mater Misericordiae Hospital,
South Brisbane, between 1920 and 1925. He was a visiting medical officer to the Blind, Deaf and Dumb Institution of Queensland. Winterbotham was a member of the Queensland branch of the
British Medical Association and helped to organise the general practitioners' group of the association in 1939. He served as chairman until 1949 and was president in 1944. He lobbied for pay rises for R.M.O.s. During
World War II, he participated in the committee which monitored wartime petrol rationing and he lectured in medical ethics at the
University of Queensland. Winterbotham was patron of the university's medical society between 1943 and 1944. == Anthropological work ==