Two sets of 20 cases were matched for abnormality presence and mammographic appearances as closely as possible. Seven radiologists and advanced practitioners then examined these cases on a GE digital mammography workstation whilst their eye movements were recorded using a head-mounted eye tracker. For 20 cases they were not allowed to manipulate the images and for the other 20 they could manipulate the images (that is, pan, zoom and adjust contrast and window level) if they wanted to. Case viewing order was randomised. For each case they rated their confidence in abnormality presence, its location, case density and their screening decisions. Their performance and search behaviour were also compared to those of an experienced radiologist who was very familiar with the case set.