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Updated: Aug 11, 2026
09:29
A Standardized Obstacle Course for Assessment of Visual Function in Ultra Low Vision and Artificial Vision
Published on: February 11, 2014
Assessment of function related to vision (AFREV)
Undraa Altangerel1, George L Spaeth, William C Steinmann
1Wills Eye Hospital/Jefferson Medical College, William & Anna Goldberg Glaucoma Service & Research Laboratories, Philadelphia, PA 19107, USA.
Ophthalmic Epidemiology
|March 3, 2006
Summary
The Assessment of Function Related to Vision (AFREV) is a new performance-based measure that shows strong correlations with standard clinical tests and patient-reported outcomes in glaucoma patients. This new visual functioning test appears to be a valid tool for assessing abilities not captured by traditional methods.
Area of Science:
- Ophthalmology
- Clinical Research
- Vision Science
Background:
- Glaucoma management relies on clinical measures and patient-reported outcomes.
- A performance-based measure can offer unique insights into visual functioning.
- The Assessment of Function Related to Vision (AFREV) is a novel tool designed to evaluate functional vision.
Purpose of the Study:
- To assess the relationship between the AFREV, a performance-based visual functioning measure, and established clinical and subjective assessments in glaucoma patients.
- To determine the validity of AFREV as a measure of functional vision in individuals with glaucoma.
Main Methods:
- A cross-sectional survey involving 43 patients diagnosed with primary open-angle glaucoma.
- Patients underwent evaluation using the AFREV, standard clinical visual function tests (visual acuity, contrast sensitivity, visual field), and the National Eye Institute's Visual Functioning Questionnaire (NEI-VFQ-25).
- Rasch analysis was employed to validate the AFREV's structure and assess patient abilities.
Main Results:
- AFREV scores demonstrated significant correlations with contrast sensitivity (r=0.772), binocular visual acuity (r=-0.768), better-eye visual acuity (r=-0.737), worse-eye visual acuity (r=-0.675), visual field efficiency (r=0.606), and NEI-VFQ scores (r=0.70).
- Rasch analysis confirmed the unidimensionality of a 5-item AFREV index, supporting its validity.
- Tasks such as 'putting stick into holes' and 'reading small print' on the AFREV required the highest levels of visual ability.
Conclusions:
- The AFREV is a valid performance-based measure that correlates well with standard clinical visual function tests and subjective quality of life assessments in glaucoma patients.
- AFREV provides valuable information on functional abilities that may not be captured by conventional clinical or self-report measures.
- This novel assessment tool holds promise for a more comprehensive evaluation of visual functioning in glaucoma.
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