A comparison of methods used to evaluate mobility performance in the visually impaired

Abstract

A validated scoring system based on errors is more effective when assessing visual disability during mobility testing than recording the time taken for course completion. The combined metric of ADREV errors noted divided by time taken was most predictive of all the methods used to evaluate visual disability during mobility testing.

Activity Limitation in Glaucoma: Objective Assessment by the Cambridge Glaucoma Visual Function Test

“…7 Recently, Warrian et al suggested improving scoring of the ADREV by incorporating time taken to complete the tasks. 34 The ADREV initially was validated against the NEIVFQ-25, which is a generic multidimensional PRO with poor specificity to glaucoma and poor fitting to the Rasch model. 16 Strengths of the CGVFT are as follows.…”

Harmonization of Outcomes and Vision Endpoints in Vision Restoration Trials: Recommendations from the International HOVER Taskforce

“…97 The main limitation currently is the lack of standardization. Orientation ability of individuals with ULV has been successfully measured with tasks, including locating the source of a bright light, walking along a line, 88,96 determining the direction of movement of a person, and locating a door. 89 These four examples are isolated tasks that have been found to be useful orientation metrics in laboratory settings.…”

“…Notably, it has been argued that the frequency of errors is equally or more predictive than speed for assessing performance on some ADLs, such as independent navigation. 96 As an alternative to recording both time and accuracy, subjects may be instructed to be as accurate as possible or as quick as possible; however, this reduces the ecological validity of the test, as subjects may not normally operate under such a constraint. Performance should be measured on a continuous scale where possible; for example, reading speed is preferred over a pass/fail score indicating whether or not the participant read the sentence correctly.…”

A novel, wearable, electronic visual aid to assist those with reduced peripheral vision

“…ADREV error score divided by time (ADREV error/time) is the most predictive measurement of visual disease, as opposed to either time taken or number of errors alone. [20]…”