Claire McKeague1, Alison M Binns, Tom H Margrain. 1. *BSc(Hons) †PhD, BSc(Hons) School of Optometry and Vision Sciences, Cardiff University, Cardiff, Wales (CMc, THM), and School of Health Sciences, City University London, London, England (AMB), United Kingdom.
Abstract
PURPOSE: To evaluate the intersession repeatability of the Colour Assessment and Diagnosis (CAD) test and a novel 14-Hz flicker test in a population of healthy participants to provide benchmark data for their use as functional biomarkers for age-related macular degeneration (AMD). METHODS: Visual function was assessed using both techniques in 30 healthy adults (mean [standard deviation] age 36.3 [14.1] years) on two separate days. Intersession repeatability of RG and YB CAD thresholds and 14-Hz flicker thresholds was assessed by determining their coefficient of repeatability (CoR). RESULTS: The CoR was calculated to be 0.39 CAD units (17.0%) for RG thresholds, 0.43 CAD units (31.1%) for YB thresholds, and 0.015 (53.4%) for 14-Hz flicker contrast thresholds. On average, thresholds improved by 4.72% (RG), 6.33% (YB), and 13.3% (14-Hz flicker) between visits 1 and 2, suggesting a small but consistent learning effect. The CoR for all parameters was relatively small compared to the mean thresholds obtained (RG: mean 2.27 [4.58], CoR 0.39; YB: mean 1.37 [0.55], CoR 0.43; 14-Hz flicker: mean 0.028 [0.01], CoR 0.015). CONCLUSIONS: This study has described the repeatability of the CAD and 14-Hz flicker tests. These data can help clinicians decide if the results from repeated measures are of clinical significance. Despite pretest training, there was some evidence of a learning effect. Therefore, clinical trials using these techniques should ensure training is sufficient to minimize these effects.
PURPOSE: To evaluate the intersession repeatability of the Colour Assessment and Diagnosis (CAD) test and a novel 14-Hz flicker test in a population of healthy participants to provide benchmark data for their use as functional biomarkers for age-related macular degeneration (AMD). METHODS: Visual function was assessed using both techniques in 30 healthy adults (mean [standard deviation] age 36.3 [14.1] years) on two separate days. Intersession repeatability of RG and YB CAD thresholds and 14-Hz flicker thresholds was assessed by determining their coefficient of repeatability (CoR). RESULTS: The CoR was calculated to be 0.39 CAD units (17.0%) for RG thresholds, 0.43 CAD units (31.1%) for YB thresholds, and 0.015 (53.4%) for 14-Hz flicker contrast thresholds. On average, thresholds improved by 4.72% (RG), 6.33% (YB), and 13.3% (14-Hz flicker) between visits 1 and 2, suggesting a small but consistent learning effect. The CoR for all parameters was relatively small compared to the mean thresholds obtained (RG: mean 2.27 [4.58], CoR 0.39; YB: mean 1.37 [0.55], CoR 0.43; 14-Hz flicker: mean 0.028 [0.01], CoR 0.015). CONCLUSIONS: This study has described the repeatability of the CAD and 14-Hz flicker tests. These data can help clinicians decide if the results from repeated measures are of clinical significance. Despite pretest training, there was some evidence of a learning effect. Therefore, clinical trials using these techniques should ensure training is sufficient to minimize these effects.
Authors: Susanne G Pondorfer; Jan H Terheyden; Helen Overhoff; Jana Stasch-Bouws; Frank G Holz; Robert P Finger Journal: Transl Vis Sci Technol Date: 2021-01-06 Impact factor: 3.283
Authors: Eleonora M Lad; Vivienne Fang; Michel Tessier; Anna Rautanen; Javier Gayan; Sandra S Stinnett; Ulrich F O Luhmann Journal: Ophthalmol Sci Date: 2022-05-20
Authors: Susanne G Pondorfer; Manuel Heinemann; Maximilian W M Wintergerst; Maximilian Pfau; Annika L Strömer; Frank G Holz; Robert P Finger Journal: PLoS One Date: 2020-04-16 Impact factor: 3.240