Clínico-efetividade e qualidade de vida visual relacionados à cirurgia de catarata no segundo olho: estudo clínico randomizado controlado

Abstract

Objectives: 1) To perform the translation and cross-cultural adaptation of the CATQUEST-9SF into Brazilian Portuguese and to analyze its psychometric properties through Rasch analysis. We also sought to evaluate the sequence of visual acuity with the answers followed with the instruction. 2) This is a randomized, controlled, non-masked clinical trial, to assess the impact obtained with cataract surgery in both eyes versus surgery in only one eye. Methods: 1) The first study involved the translation, validation and cross-cultural adaptation of the Portuguese version of the CATQUEST-9SF. This is a questionnaire unpublished in Brazil, specifically to assess the personal perception of visual quality of life in patients with cataracts. Standard translation procedures were performed in addition to its application in a Brazilian sample of 101 patients diagnosed with cataract. The psychometric properties of the instrument were evaluated using Rasch analysis. At the end, evaluation of the therapy was conducted between corrected visual acuity and the scores obtained before treatment. 2) In the second study, patients with bilateral cataract and binocular visual acuity less than or equal to 0.3 LogMAR were included. They were randomly assigned to receive surgery in one (control group) or both eyes (one eye at a time; intervention group). The main outcome of the study was the self-reported visual function obtained through the difference in scores with the CATQUEST-9SF. Stereopsis, corrected binocular visual acuity, and ocular dominance were secondary outcomes. Results: 1) The Portuguese version of the CATQUEST-9SF demonstrated acceptable adjustment of the items (item fit statistics ranging from 0.7 to 1.3), unidimensionality and good organization in the item response categories (categories thresholds: -2, 79; 0.57; 2.22). The test contains items with a stable relationship, if considered the same level of visual impairment, in the comparison between two groups (absence of Differential Item Functioning). There is adequate separation of people (Personal Separation Index 3.07). LogMAR visual acuity in the better eye with better optical correction was statistically significant with the CATQUEST-9SF logit score (r = 0.282 and p = 0.004). 2) A total of 151 patients (77 and 74 eyes in the control and intervention groups, respectively) completed the follow-up. Patients operated on both eyes had significantly better self-reported visual function (p = 0.036) and stereopsis (p = 0.026) than those who underwent surgery on one eye only. Binocular visual acuity and ocular dominance alternation were similar between the groups. Conclusions: 1) The Brazilian Portuguese version of the CATQUEST-9SF has validity and reliability, in addition to having adequate psychometric properties. Moreover, it presents a positive correlation with the visual acuity and the scores obtained in the questionnaire. 2) The self-reported visual function measured by CATQUEST-9SF and stereopsis were significantly better in patients who underwent surgery in both eyes compared to monocular surgery. Binocular visual acuity and alternation of ocular dominance were similar between the studied groups. All visual functions experience positive changes in both groups after surgery.