The paper presented by Crabtree et al in this issue of the BJO (p 519) represents yet another contribution to the growing literature on the assessment of visual function in ophthalmic patients from a variety of different settings.1-8 To date, the majority of such studies have centred on comparing the postoperative gains in visual function and visual acuity as a result of cataract surgery.9-13 Not unexpectedly, such studies have suggested that a strong correlation between visual acuity, a largely objective measure, and visual function, a relatively more subjective measure of vision, exists. For the most part too, such studies have found …