BBC Radio 4 Wednesdays 24 January to 21 February at 9 00 pm

In a society preoccupied with risk, attempts to demystify the role of epidemiologists are welcome, but a producer wishing to make an absorbing programme about epidemiologists certainly has his or her work cut out. However, Paul Arnold manages to strike a difficult balance. Exposing some interesting struggles between researchers and others, he skilfully uses these to explain and discuss some of the principles and pitfalls of epidemiological reasoning and practice.

Taking as its starting point the London cholera epidemic of 1854, the first programme tells the story of John Snow and the Broad Street pump. The historical insights, however, place Snow's pioneering natural experiment in context beside the …