Clinical utility of the K-T cancellation test in a memory clinic population. Issue 10 (25th November 2016)

• Record Type: Journal Article
• Authors: Wu, Ya-Huei; de Rotrou, Jocelyne; Sikkes, Sietske A. M.; Rigaud, Anne-Sophie; Plichart, Matthieu
• Is Part Of: Journal of clinical and experimental neuropsychology. Volume 38:Issue 10(2016)
• Page Start: 1094
• Page End: 1102
• Publication Date: 2016-11-25
• Subjects: Alzheimer's disease -- Executive function -- Mild cognitive impairment -- Neuropsychological test -- Psychometrics; Neuropsychology -- Periodicals; Psychophysiology -- Periodicals; Neurosciences -- Periodicals; Psychophysiology -- Periodicals; Societies, Medical -- Periodicals; 616.89
• DOI: 10.1080/13803395.2016.1196164
• Languages: English
• ISSNs: 1380-3395

Abstract

ABSTRACT: Background/Aim : The K-T cancellation test (K-T) has been validated as a measure of executive functions (EF) but its clinical utility has not yet been examined. This study aimed to validate K-T in a memory clinic setting by examining its capacity to discriminate older adults with normal cognition (NC) from those with mild cognitive impairment (MCI) and Alzheimer's disease (AD). Method : K-T was administered to 120 NC subjects, 146 patients with MCI, and 93 patients with AD. A one-way analysis of covariance was used to compare the correct cancellations of K-T between the groups. Linear regressions were run to identify significant demographic predictors of K-T for NC subjects and to determine the equation to calculate z scores for all subjects. The area under the curve (AUC), sensitivity (Se), specificity (Sp), and positive (PPV) and negative (NPV) predictive values were assessed to compare the diagnostic performance between K-T and the Mini-Mental State Examination (MMSE) for discrimination between NC subjects and patients with cognitive impairment. Results : After adjusting for age, education, and gender, the groups were significantly different from each other regarding the number of correct cancellations of K-T, F (2, 353) = 116.6, p < .001, η 2 p = .40. Compared to the NC group ( Z = 0, SD = 1), the mean z score was –1.52 for the MCI group and –2.53 for the AD group, suggesting impaired performance for the patient groups. K-T showed a better diagnostic performance for discrimination between the NC subjects and the patients with MCI (AUC = .83; 95% CI [.79, .88]; Se = .79; Sp = .74; PPV = .79; NPV = .74), compared to that of MMSE (AUC = .74, 95% CI [.68, .80]; Se = .68; Sp = .73; PPV = .79; NPV = .64). Conclusion : The K-T cancellation test showed a good diagnostic performance in discriminating cognitively normal older adults from cognitively impaired patients. Our findings support the clinical utility of K-T in geriatric neuropsychological assessment for detection of early cognitive impairment.