Validity of newly developed appropriateness criteria for cataract surgery

The introduction of phacoemulsification in the early 1990s significantly changed the treatment of cataract. It is possible that appropriateness criteria for cataract extraction developed before the widespread adoption of phacoemulsification no longer is as accurate or valid as possible. The objective of this study was to validate newly developed explicit appropriateness criteria.

Prospective, observational cohort study.

Consecutive patients with a diagnosis of cataract who were on waiting lists to undergo cataract extraction by phacoemulsification were recruited.

Newly developed explicit appropriateness criteria for cataract extraction, following Research and Development methodology, were applied in this study conducted in 17 public teaching hospitals. Data necessary to classify the appropriateness of the intervention, including demographic and clinical data and that related to the surgery and complications, were recorded by previously trained ophthalmologists in all centers before the intervention and at the 6-week visit afterward.

Subjects completed 2 questionnaires that measure health-related quality of life--the Short Form 36 and the Visual Function Index 14 (VF-14)--before the procedure and 3 months afterward. Also, visual acuity was recorded by ophthalmologists previous to the intervention and at 6 weeks after.

Five thousand two hundred fifty-seven cases were included in the study. At 3 months after cataract extraction, 4335 (82.5%) patients had responded to the questionnaires. Patients whose procedures were classified as necessary or appropriate by the new appropriateness criteria had greater improvements in visual acuity and VF-14 scores than those undergoing procedures classified as inappropriate. These differences seemed to be clinically relevant by measures such as the minimal clinically important difference and minimal detectable change. Complications rates were similar among all appropriateness categories, except for complications occurring in the peri-intervention period.

These results suggest a direct relationship between the newly developed explicit appropriateness criteria for cataract extraction and outcomes, as measured by clinical evaluation and health-related quality-of-life instruments. The results support the use of these criteria for clinical evaluation or the development of clinical guidelines.