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Purpose To develop a novel vision‐ related quality‐ of‐ life questionnaire for patients with low vision. Methods The content for questionnaire items was determined through personal interview with patients facing various ocular diseases (aAge‐ rRelated mMacular dDegeneration, dDiabetic rRetinopathy, etc.) and with bBest cCorrected vVisual aAcuity (BCVA) ranging from light perception to 0.2 logMAR. Patients were asked to define the most important activities in their everyday lives and difficulties due to their visual impairment. Analysis following interview identified groups of items which formed the questionnaire's scales and subscales that were evaluated for internal consistency. All eligible persons had to be 18 years or older and cognitively able to give informed consent for participation. Results Fifty patients with a mean (standard deviation, SD) age of 54.6 (29.9) years were studied. Items that were internally inconsistent, unreliable or not relevant were excluded, resulting in the 50‐item quality‐ of‐ life and independence assessment questionnaire. Items were distributed into 7 different functional visual domains: mobility under various luminance conditions, self‐care, shopping, communication, social life, technology and education–‐work life. There were no significant differences among patients regarding their general health (p = 0.444). The questionnaire was proved to have a good internal consistency (Cronbach's alpha > 0.8). The average score of patients with low vision was significantly lower (p < 0.001) than the average score of those with BCVA > 0.5 logMAR and significantly higher (p < 0.001) than those with BCVA < 1.3 logMAR. Conclusions There is preliminary evidence that questionnaire has good internal consistency (alpha > 0.8, n = 50). Results also suggest that the questionnaire seems to be sensitive to subgroup differences by measuring the vision‐ related quality of life and independence. The instrument is going to be further refined following this pilot study.

PurposeLow vision (LV) is one of the major causes affecting detrimentally the quality of life of individuals. There are various underlying ocular pathologies resulting in LV. The purpose of this study is to determine the prevalence of the main causes of low vision in a population attended a university outpatient unit in Greece.MethodsThe records of all patients within a timeframe of about 18 months period were retrospectively reviewed. In this study, individuals with best‐corrected visual acuity (BCVA) of 3/60 to <6/18 were characterized as having LV, according to the World Health Organization (WHO) definition of LV.ResultsTwo hundred thirty‐six LV patients were included—114 (48.3%) were males and 122 (51.7%) females. The age of patients ranged from ten to ninety‐nine, with a mean age of 70.9 ± 18.9 years. BCVA ranged from 1.32 logMAR to 0.33 logMAR, with a mean VA of 0.7152 ± 0.3146 logMAR in the better eye. The distribution of LV causes in this population was the following: Age‐related macular degeneration (AMD) accounting for 50.0% of the cases (118/236), diabetic retinopathy (DR) 19.9% (47/236) and glaucoma 7.2% (17/236). Other causes of LV included retinitis pigmentosa in a percentage of 5.3% and other hereditary retinal diseases (3%), previous retinal detachment (2.5%), other maculopathies (2.1%) and various other ocular diseases (9.7%). Out of 118 patients with AMD, 75 (64.1%) had the dry form and 42 (35.9%) had the wet form of the disease and among patients with diabetic retinopathy as underlying cause of LV, 31 (68.9%) had the proliferative and 14 (31.1%) had the non‐proliferative form of the disease.ConclusionsAge‐related macular degeneration, diabetic retinopathy and glaucoma constituted the three main causes of low vision in the study population, followed by other ocular diseases.

Low vision (LV) has a substantial impact on an individual’s daily functionality and patient-reported outcome measures (PROMs) are increasingly incorporated into the evaluation of this problem. The objective of this study was to describe the design of the new “Life for Low Vision Questionnaire (LIFE4LVQ)”, as a measure of daily functionality in LV and to explore its psychometric properties. A total of 294 participants completed the LIFE4LVQ and the data were subjected to Rasch analysis to determine the psychometric properties of the questionnaire, including response category ordering, item fit statistics, principal component analysis, precision, differential item functioning, and targeting. Test–retest reliability was evaluated with an interval of three weeks and intraclass correlation coefficients (ICC) were used. The correlation between the questionnaire score and Best Corrected Visual Acuity (BCVA) was examined using Spearman’s correlation coefficient. Rasch analysis revealed that for most items the infit and outfit mean square fit values were close to 1, both for the whole scale and its subscales (ability and independence). The separation index for person measures was 5.18 with a reliability of 0.96, indicating good discriminant ability and adequate model fit. Five response categories were found for all items. The ICC was 0.96 (p < 0.001; 95% CI, 0.93–0.98), suggesting excellent repeatability of the measure. Poorer BCVA was significantly associated with worse scores (rho = 0.559, p < 0.001), indicating excellent convergent validity. The functional, 40-item LIFE4LVQ proved to be a reliable and valid tool that effectively measures the impact of LV on ability and independence.

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