Development of the Vision Impairment in Low Luminance Questionnaire.

Purpose: The purpose of this study was to design and evaluate an instrument for assessing vision-related quality of life appropriate for the specific visual impairment characteristic for all stages of age-related macular degeneration (AMD), with a focus on the low luminance deficit in early/intermediate stages.

Methods: A standardized questionnaire was developed in three steps with participants with early, intermediate, and late AMD: (1) based on in-depth interviews ( = 19) and two focus group discussions ( = 5 each), content was developed followed by 2. (2) The questionnaire development using cognitive debriefing interviews ( = 3) and leading to a preliminary version of the questionnaire.