gms | German Medical Science

Visual acuity alone is not an adequate measure of visual impairment. Therefore visual-related quality of life based on functional assessments can give valuable additional information especially for evidence based medical investigations. We formulated and validated German versions of the VF-14 test and the National Eye Institute Visual Function Questionnaire 25 (VFQ-25).

The original English questionnaires were translated into German and back into English by four independent translators. Using these questionnaires, a survey was conducted with 47 patients who had undergone corneal transplantation, by interviewing them over the telephone. Demographics, ocular history, visual acuity and ocular examination data of the patients were collected.

The average age of the patients was 42.7±16.3 years (range 17 to 77 years) and 70% were male. The mean VFQ-25 score was 78.0±18.5 (VF-14 score: 87.7±16.9) and internal consistencies were high, with a Cronbach α value of 0.88 (0.76). The consistency between the two tests was high, with a Cronbach α value of 0.92. The mean test results differed significantly (p<0.01), so that possible test results ranging between 0 to 100 cannot be directly compared. Female patients had a significantly lower test score in both tests. There was no difference in the test score on comparing patients living alone with patients living with their families.

The German version of the VF-14 and the VFQ-25 questionnaires is a valid measures of functional visual impairment. The German test version can be used in clinical research as a specific measure of quality of life in patients with eye diseases.