Sir Iain practised as a clinician for seven years in the UK and the Gaza Strip, before becoming a full time health services researcher. He was founding director of both the National Perinatal Epidemiology Unit and the UK Cochrane Centre. Since 2003, he has coordinated the James Lind Initiative to promote public and professional acknowledgement of the need to address uncertainties about the effects of treatments. He is coordinating editor of The James Lind Library and Testing Treatments Interactive. He was knighted in 2000 for services to health care.

All of us are exposed regularly to claims about the effects of interventions alleged to protect and promote health. Why is it important to ask whether these claims are reliable? And how can all of us be helped to assess which of the claims are likely to be trustworthy?

From a very early age, children ask very reasonable ‘Why?’ questions. What can be done to encourage children’s ‘innate’ curiosity about how the world works? How can critical thinking about the answers offered to them be promoted? In particular, how might children and young people be introduced to concepts that would prompt them to ask probing questions about the reliability of claims about the effects of interventions? Finally, how should the effects of efforts to help children and young people to become effective BS detectives be assessed?