MB BChir Cambridge 1963, MA 1966; FRCS Eng 1969; FRCS Edin 1967.
After qualifying, Clegg held junior positions at MRI and was assistant lecturer in physiology at the University of Manchester in 1965. He then held appointments as surgical registrar at Hammersmith Hospital London and Park Hospital Davyhulme, and was senior registrar at MRI. Clegg was later appointed consultant surgeon at Leighton Hospital and Royal Victoria Infirmary, Northwich, Cheshire. Clegg was a fellow of Manchester Medical Society and a member of the British Society of Gastroenterology, the Royal Society of Medicine, the International Societe de Chirurgie, the Vascular Society of Great Britain and Ireland and a fellow of the International College of Angiology.