Analysis of methods of providing anonymity in facial photographs; a randomised controlled study

Abstract

Clinical images are invaluable in medical teaching and research publications. In the past efforts to conceal patient identity, if any, were limited to a black bar concealing the eyes. However, there is no consensus on this among major journals and publishing houses. This research analyses the effectiveness of blacking out the eyes in facial photographs and evaluates alternative techniques. 126 questionnaires were completed. The average numbers of correct responses out of 30 was 24.64 (82.13%) in the control group, 20.59 (68.63%) in the eyes, 20.42 (68.07%) in the eyes and nose group, and 17.53 (58.43%) in the T-shaped group (eyes, nose and mouth). The traditional method of covering the eyes does significantly decrease recognition, however it is only as effective as covering the nose and mouth. The more of the face that is covered the less likely it is that the person is recognised. However, there are people who remain identifiable no matter how much of the face is covered. This work highlights the importance of obtaining consent prior to publication as well as attempting to hide identity.