Development and Validation of Performance-Based Assessment of Daily Living Tasks in Age-Related Macular Degeneration

To establish the reliability and validity of five performance-based activities of daily living task tests (ADLTT), to correlate structure to function, to evaluate the impact of visual impairment (VI) on age-related macular degeneration (AMD), and to develop new outcome measures.

A multidisciplinary team developed five ADLTTs: (1) reading test (RT); (2) facial expression (FE) recognition; (3) item search (IS) task; (4) money counting (MC) task; and (5) making a drink (MD), tested with binocular and monocular vision. ADLTTs were tested for known-group (i.e., difference between AMD group and controls) and convergent (i.e., correlation to other measures of visual function), validity metrics, and test-retest reliability in 36 patients with VI (visual acuity (logMAR VA > 0.4) in at least one eye caused by AMD versus 36 healthy controls without VI.

Compared to controls, AMD patients had a slower reading speed (-77.41 words/min; P < 0.001); took longer to complete MC using monocular worse eye and binocular vision (15.13 seconds and 4.06 seconds longer compared to controls, respectively; P < 0.001); and MD using monocular worse eye vision (9.37 sec; P = 0.033), demonstrating known-group validity. Only RT and MC demonstrated convergent validity, showing correlations with VA, contrast sensitivity, and microperimetry testing. Moderate to good test-retest reliability was observed for MC and MD (interclass correlation coefficient = 0.55 and 0.77; P < 0.001) using monocular worse eye vision.

Real-world ADL functioning associated with VI-related AMD can be assessed with our validated ADLTTs, particularly MC and MD.

This study validates visual function outcome measures that are developed for use in future clinical practice and clinical trials.