Reliability of the NACC Telephone‐administered Neuropsychological Battery (T‐cog) and Montreal Cognitive Assessment for participants in the USC ADRC

INTRODUCTION: Restrictions during the COVID‐19 pandemic necessitated remote administration of neuropsychological testing. We assessed the test–retest reliability for a telephone‐administered cognitive battery, recommended for use in the National Institute on Aging Alzheimer's Disease Research Center (ADRC). METHODS: 64 participants in the University of Southern California ADRC clinical core underwent repeat telephone evaluation using the T‐cog Neuropsychological Battery. Reliability was measured by intraclass correlation coefficient (ICC) for continuous variables and weighted Kappa coefficient for categorical variables. Mean scores for Montreal Cognitive Assessment (MoCA) total and Craft Story 21 Immediate and Delayed Recall were compared using paired t tests. RESULTS: Mean age was 74.8 (8.3 standard deviation); 73.4% were female. ICCs ranged from 0.52 to 0.84, indicating moderate test–retest reliability except for number span backward, which showed poor reliability. Weighted Kappa for MoCA items ranged from −0.016 to 0.734; however, relatively good observed agreement was seen across all items (70.3% to 98.4%). Although MoCA total scores did not significantly change, Craft Story 21 Immediate and Delayed Recall mean scores increased between first and second administrations (P < 0.0001). DISCUSSION: Test–retest reliability for the T‐cog Neuropsychological Battery is adequate. The variation seen in testing is similar to results seen from face‐to‐face testing, with Craft Story 21 recall showing modest and expected practice effects. HIGHLIGHTS: Moderate test–retest reliability is seen in most measures of the National Alzheimer's Coordinating Center Neuropsychological Test Battery and the Montreal Cognitive Assessment (MoCA). Intraclass correlation coefficients ranged from 0.52 to 0.84, except for number Span backward. Weighted Kappa for MoCA items varied, but good observed agreement was seen. MoCA total mean score did not change significantly between administrations. Craft Story 21 Immediate and Delayed Recall means increased on repeat testing (P < 0.0001).