Born 9 April 1881, son of Hugh McCaw, MB CM Glasgow 1877, in practice at East Taieri, Otago, New Zealand, and Jane Macadam Todd, his wife. He was educated at the Otago Boys' High School and at Otago College, University of New Zealand, before coming to England to study medicine. He entered the London Hospital in 1905, qualified in 1908, served as house surgeon and pathological assistant at the London, and also worked at the Seamen's Hospital, Greenwich. He took the Fellowship at the end of 1911, and during 1911-12 was senior resident surgical officer at the Bristol Royal Hospital for Children and Women. Returning to New Zealand he practised at 57 Don Street, Invercargill, and became surgeon to the Southland Hospital there. During the first world war he saw active service for two years in France, being commissioned captain in the New Zealand Army Medical Corps on 13 August 1917 and attached to the New Zealand artillery. He then returned to his work in New Zealand. In 1929 he was elected a Fellow of the Royal Australasian College of Surgeons, and in 1934-36 he was chairman of the Southland division of the New Zealand branch of the British Medical Association. McCaw married on 31 March 1919 Mary, daughter of the Rev S Campbell Fry, minister of Girvan, Scotland. He died at Otago on 21 June 1943, survived by his wife; there were no children.