Is there overutilisation of cataract surgery in England?
- 1Health Services Research Unit, London School of Hygiene & Tropical Medicine, London, UK
- 2Clinical Effectiveness Unit, Royal College of Surgeons of England, London, UK
- 3Department of Public Health, University of Glasgow, Glasgow, UK
- Professor N Black, Professor of Health Services Research, Health Services Research Unit, London School of Hygiene & Tropical Medicine, London WC1E 7HT, UK;
- Accepted 30 March 2008
Objectives: Following a 3.7-fold increase in the rate of cataract surgery in the UK between 1989 and 2004, concern has been raised as to whether this has been accompanied by an excessive decline in the threshold such that some operations are inappropriate. The objective was to measure the impact of surgery on a representative sample of patients so as to determine whether or not overutilisation of surgery is occurring.
Design: Prospective cohort assessed before and 3 months after surgery.
Setting: Ten providers (four NHS hospitals, three NHS treatment centres, three independent sector treatment centres) from across England.
Participants: 861 patients undergoing first eye (569) or second eye (292) cataract surgery provided preoperative data of whom 745 (87%) completed postoperative questionnaires.
Main outcome measures: Patient-reported visual function (VF-14); general health status and quality of life (EQ5D); postoperative complications; overall view of the operation and its impact.
Results: Overall, visual function improved (mean VF-14 score increased from 83.2 (SD 17.3) to 93.7 (SD 13.2)). Self-reported general health status deteriorated (20.3% fair or poor before surgery compared with 25% afterwards) which was reflected in the mean EQ5D score (0.82 vs 0.79; p = 0.003). At least one complication was reported by 66 (8.9%) patients, though this probably overestimated the true incidence. If the appropriateness of surgery is based on an increase in VF-14 score of 5.5 (that corresponds to patients’ reporting being “a little better”), 30% of operations would be deemed inappropriate. If an increase of 12.2 (patients’ reports of being “much better”) is adopted, the proportion inappropriate is 49%. Using a different approach to determining a minimally important difference, the proportion inappropriate would be closer to 20%. Although visual function (VF-14) scores were unchanged or deteriorated in 25% of patients, 93.1% rated the results of the operation as “good,” “very good” or “excellent,” and 93.5% felt their eye problem was “better.” This partly reflects inadequacies in the validity of the VF-14.
Conclusions: Improvement in the provision of cataract surgery has been accompanied by a reduction in the visual function threshold. However, methodological difficulties in measuring the impact of cataract surgery on visual function and quality of life mean it is impossible to determine whether or not overutilisation of cataract surgery is occurring.
Competing interests: None.
Funding: The sponsor (the Department of Health Policy Research Programme and Commercial Directorate) had no part or influence on any aspect of this study, the writing of the report or the decision to submit the article for publication.
Contributors: NB, JB, JvdM and JL designed the study; LJ and LC managed data collection and cleaning; JL conducted statistical analyses; NB drafted the paper; JB, JvdM and JL commented and contributed to the final version. NB is guarantor.
Ethics approval: Ethics approval was provided by Wales MREC.
Patient consent: Obtained.