Abstract
The Benton Visual Form Discrimination Test (VFDT) is a commonly used measure of visual discrimination and visual recognition memory and has shown promise in distinguishing between different levels of cognitive impairment. We assess the predictive diagnostic utility of the VFDT in a sample of older Veterans with cognitive concerns.
Subjects included a total of 172 mostly male Veterans over the age of 64 (mean = 76.0; SD = 7.6) recruited from a VA clinic specializing in neuropsychological assessment of older Veterans. The clinical sample included 56 subjects diagnosed with Major Neurocognitive Disorder, 74 diagnosed with Mild Neurocognitive Disorder, and 42 with No Neurocognitive Impairment. Impairment categories were modeled in separate multinomial logistic regressions with two versions of the VFDT as predictors: the Visual Form Discrimination Test-Recognition Subtest (VFDT-Rec) test (visual recognition memory) and the Visual Form Discrimination Test-Matching Subtest VFDT-Mat test (visual form discrimination). Years of education were included as a covariate.
After adjusting for education, higher VFDT-Rec total scores were associated with lower odds of being categorized with a greater degree of cognitive/functional impairment (OR 0.66–0.83, p < .001). VFDT-Mat scores showed a similar pattern, but only reached statistical significance for the Major versus No Neurocognitive Impairment (OR = 0.77, p = .0010) and Major versus Mild comparisons (OR = 0.89, p = .0233).
The VFDT may enhance the confidence of differential diagnosis of dementia in older adult Veterans. Formal education-adjusted norms need to be established for clinical use.
