The development and validation of a questionnaire to assess visual symptoms/dysfunction and impact on quality of life in cataract patients: the Visual Symptoms and Quality of life (VSQ) Questionnaire

Abstract

The aim of the study was to develop a new questionnaire to assess visual symptoms/dysfunction and impact on vision-specific quality of life for those undergoing second eye cataract extraction. Items for the VSQ questionnaire were devised with reference to existing literature and following consultation with eye care experts (n = 18) and interviews with cataract patients (n = 40). Piloting work conducted with 53 patients indicated that the questionnaire was promising, with a high level of internal consistency, low levels of missing data and indications that it was responsive to surgery. A modified version of the questionnaire was completed by 105 patients having received ‘early’ surgery and 103 scheduled for routine surgery within a randomized controlled trial evaluating the effectiveness of second eye cataract surgery. Analyses showed that the internal consistency of both the visual symptoms/dysfunction and quality of life areas was high (Cronbach's alpha 0.82 and 0.83, respectively). Highly significant improvements were found for early surgery patients (p < 0.0001), with little change among routine surgery patients. Two final versions of the VSQ questionnaire have been produced for future use in assessing visual symptoms/dysfunction and impact on vision-specific quality of life: a scoreable short form and more detailed and sensitive long form.