Abstract

Three new techniques are presented for assessing visual acuity in the presence of suspected malingering. The first technique is based on the preferential looking method commonly used to test acuity in infants. The second uses polarising filters to present stimuli briefly to both eyes or to each eye alone, without the patient's being aware of which eye is tested. The third presents the stimuli on a computer monitor and separates the ray paths of the two eyes by means of special spectacles that obscure vision in one eye for fractions of a second while a stimulus is presented.