Despite major advances in our understanding of the burden and epidemiology of childhood acute respiratory infections, almost two million children still die from pneumonia each year, accounting for 20% of deaths in children aged under 5 years globally.¹² Accurate figures are difficult to obtain, but the estimated incidence of pneumonia is 151 million new cases a year, and, of these, some 11-20 million (7-13%) are severe enough to require hospitalisation.2 These composite figures do not reflect the tremendous inequity both between and within countries, with the bulk of pneumonia deaths affecting the poor with limited access to services.3

The crucial first step in tackling childhood pneumonia is being able to diagnose it accurately, a challenge highlighted in this week's BMJ by Hazir and colleagues.4 They analysed 1848 chest radiographs of children in Pakistan hospital outpatient settings who had had non-severe pneumonia diagnosed clinically …