BA Cambridge 1976, MB BChir 1979; MSc Manch 1988; MFPHM 1988.
After qualifying, Chisholm held junior positions at Hastings Hospital, King's College Hospital and Utraula Hospital, India. In 1982 Chisholm undertook research into failures of the cervical screening programme for the University of Manchester Department of Epidemiology and Social Research. She was then registrar at Cheadle Royal and Withington Hospitals and Central Manchester Health Authority. From 1986 to 1989 Chisholm was senior registrar in community medicine for the North West Regional Health Authority, undertaking various long placements, later becoming consultant in public health medicine. In 1991 Chisholm was appointed Director of Public Health for Central Manchester Health Authority and honorary lecturer for the Department of Public Health and Epidemiology at the University of Manchester.