‘All screening programmes do harm; some do good as well, and, of these, some do more good than harm at reasonable cost’ (Gray et al. 2008). The routine recalling of people for sight tests has certain similarities to screening. This is because asymptomatic people are called by a healthcare professional to have an intervention, the aim of which is, partly, to ascertain their health. This is quite different from leaving people to have a sight test only when they have symptoms or concerns about their eyes. It is therefore important to consider whether this practice does more harm than good.