The VQL-6 questionnaire was developed to gain insight into the vision-related quality of life and signal a need for additional care in patients with chronic ophthalmic diseases. The VQL-6 includes items that were chosen based on their association with quality of life and a need for additional care.
26 A need for additional care may be multifaceted and influenced by various factors, including mental health, comorbidities, coping, and social support, areas that are reflected in the VQL-6.
14,15,27,28 The questionnaire items were carefully defined by a multidisciplinary team of experts in the field of visual rehabilitation and ophthalmology. We constructed novel items and reviewed existing questionnaires, including the NEI-VFQ-25, for relevant items that were adapted to fit the aim of our questionnaire.
The VQL-6 comprises six items. On items 1, 2, and 3 respondents are asked to indicate, on a scale of 0 to 10, their (1) general health, (2) general quality of life, and (3) the extent of experienced limitations by their visual impairment. The subsequent items measured whether the respondent, because of their visual impairment, (4) worries about the future, (5) feels like he/she accomplishes less, and (6) feels dependent on others. Items 4, 5, and 6 were scored on a 5-point Likert scale with answer options never, rarely, sometimes, often, and always. Respondents are instructed to answer the questions based on their situation in the past month while considering their use of glasses or contact lenses, if applicable. For analysis, all VQL-6 items were converted to a 0 to 10 scale (by transforming the 5-point Likert scale answer options to 0, 2.5, 5.0, 7.5, and 10.0) to ensure all items received equal weight. In addition, all items were transformed so that a higher score represents better functioning to enable a fair comparison between items.