Ivan Sencanic1, Tatjana Gazibara2, Jelena Dotlic3, Miroslav Stamenkovic1,4, Vesna Jaksic1,3, Marija Bozic3,5, Anita Grgurevic2. 1. Clinic for Eye Disease "Prof. dr Ivan Stankovic", University Medical Center "Zvezdara", Belgrade 11050, Serbia. 2. Institute of Epidemiology, Faculty of Medicine, University of Belgrade, Belgrade 11129, Serbia. 3. Faculty of Medicine, University of Belgrade, Belgrade 11129, Serbia. 4. Faculty of Special Education and Rehabilitation, University of Belgrade, Belgrade 11000, Serbia. 5. Clinic for Eye Disease "Prof. dr Djordje Nesic", Clinical Center of Serbia, Belgrade 11129, Serbia.
Abstract
AIM: To translate the Glaucoma Quality of Life-15 (GQL-15) to Serbian language and asses its validity and reliability in the population of Serbian patients. METHODS: The study included 177 glaucoma patients. Clinical parameters (visual acuity, mean defect and square root of loss variance of visual field) and socio-demographic data were collected. Patients were stratified according to the Nelson's glaucoma staging system as mild, moderate and advanced glaucoma. All patients filled out the GQL-15 and National Eye Institute Visual Function Questionnaire (NEI-VFQ 25). The GQL-15 was translated following the internationally-accepted methodology, and its psychometric properties were assessed by using classical test theory and Rasch analysis. RESULTS: The mean total score for the GQL-15 was 20.68±7.31. The Cronbach's alpha coefficient for the whole scale was 0.89 (central and near vision, α=0.24; peripheral vision, α=0.85; glare and dark adaptation, α=0.83). Factor analysis established 4 factors (70.3% of variance): two corresponding to the original factors and two new factors specific for the Serbian population. The GQL-15 score correlated positively with almost all clinical parameters and NEI-VFQ 25 proving good criterion validity. Correlation of the GQL-15 total score on test-retest confirmed appropriate scale reproducibility (ρ=0.96, P<0.001). The GQL-15 discriminated well advanced from mild and moderate glaucoma. In Rasch analysis we obtained adequate item (0.95) reliability index. Almost all items had infit and outfit mean squares in the accepted range. CONCLUSION: Serbian version of the GQL-15 demonstrates adequate reliability and validity. This version of the GQL-15 is a valid instrument for evaluation of quality of life among Serbian speaking patients with glaucoma and can be applied in daily clinical work.
AIM: To translate the Glaucoma Quality of Life-15 (GQL-15) to Serbian language and asses its validity and reliability in the population of Serbian patients. METHODS: The study included 177 glaucomapatients. Clinical parameters (visual acuity, mean defect and square root of loss variance of visual field) and socio-demographic data were collected. Patients were stratified according to the Nelson's glaucoma staging system as mild, moderate and advanced glaucoma. All patients filled out the GQL-15 and National Eye Institute Visual Function Questionnaire (NEI-VFQ 25). The GQL-15 was translated following the internationally-accepted methodology, and its psychometric properties were assessed by using classical test theory and Rasch analysis. RESULTS: The mean total score for the GQL-15 was 20.68±7.31. The Cronbach's alpha coefficient for the whole scale was 0.89 (central and near vision, α=0.24; peripheral vision, α=0.85; glare and dark adaptation, α=0.83). Factor analysis established 4 factors (70.3% of variance): two corresponding to the original factors and two new factors specific for the Serbian population. The GQL-15 score correlated positively with almost all clinical parameters and NEI-VFQ 25 proving good criterion validity. Correlation of the GQL-15 total score on test-retest confirmed appropriate scale reproducibility (ρ=0.96, P<0.001). The GQL-15 discriminated well advanced from mild and moderate glaucoma. In Rasch analysis we obtained adequate item (0.95) reliability index. Almost all items had infit and outfit mean squares in the accepted range. CONCLUSION: Serbian version of the GQL-15 demonstrates adequate reliability and validity. This version of the GQL-15 is a valid instrument for evaluation of quality of life among Serbian speaking patients with glaucoma and can be applied in daily clinical work.
Authors: Bojan Kovac; Miroslav Vukosavljevic; Jelena Djokic Kovac; Mirko Resan; Goran Trajkovic; Janko Jankovic; Milena Smiljanic; Anita Grgurevic Journal: Health Qual Life Outcomes Date: 2015-09-15 Impact factor: 3.186
Authors: Jamie Enoch; Lee Jones; Deanna J Taylor; Carol Bronze; James F Kirwan; Pete R Jones; David P Crabb Journal: Eye (Lond) Date: 2019-12-10 Impact factor: 3.775