A comparison of neuropsychological performance between US and Russia: Preparing for a global clinical trial. Alzheimer’s & Dementia, July 22, 2014. Kathleen M. Hayden, Oksana A. Makeeva, L. Kristin Newby, Brenda L. Plassman, Valentina V. Markova, Ashley Dunham, Heather R. Romero, Zarui A. Melikyan, Cassandra M. Germain, Kathleen A. Welsh-Bohmer, Allen D. Roses, on the behalf of the TOMSK-DUKE Study Group Investigators.
Author Affiliations:
- Department of Psychiatry, Joseph and Kathleen Bryan ADRC, Duke University Medical Center, Durham, NC, USA
- Duke Clinical Research Institute, Durham, NC, Department of Medicine, Duke University Medical Center, Durham, NC, USA,
- Department of Psychiatry, Joseph and Kathleen Bryan ADRC, Duke University Medical Center, Durham, NC, USA
- Center for Clinical Trials, Nebbiolo LLC, Tomsk, Russia
- Duke Clinical Research Institute, Durham, NC, USA,
- Department of Psychiatry, Joseph and Kathleen Bryan ADRC, Duke University Medical Center, Durham, NC, USA
- Center for Clinical Trials, Nebbiolo LLC, Tomsk, Russia
- Department of Psychiatry, Joseph and Kathleen Bryan ADRC, Duke University Medical Center, Durham, NC, USA
- Department of Psychiatry, Joseph and Kathleen Bryan ADRC, Duke University Medical Center, Durham, NC, USA
- Zinfandel Pharmaceuticals, Durham, NC, USA, on the behalf of the TOMSK-DUKE Study Group Investigators
Background
Understanding regional differences in cognitive performance is important for interpretation of data from large multinational clinical trials.
Methods
Data from Durham and Cabarrus Counties in North Carolina, USA and Tomsk, Russia (n = 2972) were evaluated. The Montreal Cognitive Assessment (MoCA), Trail Making Test Part B (Trails B), Consortium to Establish a Registry for Alzheimer’s Disease Word List Memory Test (WLM) delayed recall, and self-report Alzheimer’s Disease Cooperative Studies Mail-In Cognitive Function Screening Instrument (MCFSI) were administered at each site. Multilevel modeling measured the variance explained by site and predictors of cognitive performance.
Results
Site differences accounted for 11% of the variation in the MoCA, 1.6% in Trails B, 1.7% in WLM, and 0.8% in MCFSI scores. Prior memory testing was significantly associated with WLM. Diabetes and stroke were significantly associated with Trails B and MCFSI.
Conclusions
Sources of variation include cultural differences, health conditions, and exposure to test stimuli. Findings highlight the importance of local norms to interpret test performance.
