Lalit Dandona MD MPH Director International Centre for Advancement of

Cataract outcome is the result of surgi-cal intervention for visual impairment or blindness due to cataract. It can be measured as visual acuity in the operated eye or in the patient, in terms of function, as quality of life and as economic rehabili-tation.Of these,visualacuityismost suited to measure performance and monitor quality of service. Clinical Trials: India and Nepal Table 1 shows the outcome of cataract surgery in clinical trials under optimal conditions. More than 90 % of eyes with cataract achieve a best-corrected visual acuity of 6/18 or better. The variation in visual outcome between various surgical techniques is minimal. Less than 3 % of the operated patients had a best-corrected vision of less than 6/60. These clinical trial results may reflect one end of the spec-trum, suggesting what may be possible in an ideal setting under very controlled circumstances. While setting general stan-dards for hospitals in a developing country situation, this aspect would have to taken into account. Population-based Surveys in Asia However, recent population-based surveys have shown that of all the patients operated on for cataract, 21Ð53 % had a presenting visual acuity of less than 6/60. With best correction, 11Ð21 % still had acuity less than 6/60 (Table 2). These figures include patients operated on recently as well as those who had surgery decades earlier. They include operations done under excel-lent as well as less favourable conditions, by experienced as well as less experienced eye surgeons. In brief, these results reflect the vision after cataract surgery in a cross-section of the population. WHO Workshop on Outcomes, 1998 Poor visual acuity following surgery will affect the demand and uptake of cataract surgical services. Concerned about these results, the World Health Organization convened a workshop on Outcome in Pre