NIKE: a new clinical tool for establishing levels of indications for cataract surgery

Abstract

ABSTRACT.Purpose: The purpose of this study was to construct a new clinical tool for establishing levels of indications for cataract surgery, and to validate this tool. Methods: Teams from nine eye clinics reached an agreement about the need to develop a clinical tool for setting levels of indications for cataract surgery and about the items that should be included in the tool. The tool was to be called 'NIKE' (Nationell Indikationsmodell fo¨r Kataraktextraktion). The Canadian Cataract Priority Criteria Tool served as a model for the NIKE tool, which was modified for Swedish conditions. Items included in the tool were visual acuity of both eyes, patients' perceived difficulties in day-to-day life, cataract symptoms, the ability to live independently, and medical ⁄ ophthalmic reasons for surgery. The tool was validated and tested in 343 cataract surgery patients. Validity, stability and reliability were tested and the outcome of surgery was studied in relation to the indication setting. Results: Four indication groups (IGs) were suggested. The group with the greatest indications for surgery was named group 1 and that with the lowest, group 4. Validity was proved to be good. Surgery had the greatest impact on the group with the highest indications for surgery. Test-retest reliability test and interexaminer tests of indication settings showed statistically significant intraclass correlations (intraclass correlation coefficients [ICCs] 0.526 and 0.923, respectively). Conclusions: A new clinical tool for indication setting in cataract surgery is presented. This tool, the NIKE, takes into account both visual acuity and the patient's perceived problems in day-to-day life because of cataract. The tool seems to be stable and reliable and neutral towards different examiners.

Objective functional visual outcomes of cataract surgery in patients with good preoperative visual acuity

“…In particular, the Preferred Practice Guideline of the American Academy of Ophthalmology 1 and the RAND Appropriateness Methodology 2 both emphasize the importance of assessing visual function when determining the need for cataract surgery, while other guidelines were based on expert advice. 3,4 In China, a widely accepted criterion for cataract surgery is that the best-corrected visual acuity (BCVA) of the patient is lower than 20/40. 5 However, there are always a proportion of cataract patients who have good preoperative visual acuity but complain of poor vision.…”

Psychophysical impact and optical and morphological characteristics of symptomatic non-advanced cataract

“…22 The questionnaire was self-administered, but the examiner was available to answer patients' queries in relation to any of the questionnaire items. A copy of the items in the Priquest questionnaire is given in Table 1.…”

“…17 Consequently, it has been suggested that VA is not the most appropriate tool to investigate the impact of symptomatic non-advanced cataract on visual function and experience, 11 and complementary and/or alternative techniques that have been investigated include CS, 18 glare disability (GD), 19 reading performance, 20 and functional visual difficulty assessed by various questionnaires. [21][22][23] Morphological and optical characteristics of lens opacification are also important, and can be assessed by various grading systems 24 and Scheimpflug photography, 25,26 respectively, and have the advantage of being independent of patient cooperation and ocular co-morbidity.…”

Prognostic Indicators and Outcome Measures for Surgical Removal of Symptomatic Nonadvanced Cataract

“…12 Rasch analysis was applied to the questionnaire data using commercial software (WINSTEPS Rasch measurement computer program, version 3.70.0.2; Beaverton, Oregon [http://www.Winsteps.com]), thus calibrating item difficulty and patient ability on the same scale. 34,35 We found a significant gain in precision after Rasch scaling of the questionnaire (a gain of 32% and a relative precision of 1.32), thus reinforcing the current evidence with respect to the benefits of subjecting questionnaires to Rasch scaling.…”