Normative Data of Mini-Mental State Examination, Montreal Cognitive Assessment, and Alzheimer's Disease Assessment Scale-Cognitive Subscale of Community-Dwelling Older Adults in Taiwan.

INTRODUCTION: Appropriate tools and references are essential for evaluating individuals' cognitive levels. This study validated the Taiwan version of the Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-cog) and provided normative data for the Mini-Mental State Examination (MMSE), the Montreal Cognitive Assessment (MoCA), and ADAS-cog in community-dwelling older adults. METHODS: MMSE, MoCA, and ADAS-cog were administered to 150 nondemented healthy adults aged 55-85 years during 2018-2020 as part of the Northeastern Taiwan Community Medicine Research Cohort. ADAS-cog was translated from the original English version to traditional Chinese with cultural and language considerations in Taiwan. Cronbach's alpha (α) tested the reliability of ADAS-cog, and Pearson correlations examined its external validity using MMSE and MoCA as comparisons. Normative data were generated and stratified by age and education, and the one-way analysis of variance compared scores between age and education groups. Another 20 hospital-acquired participants with cognitive impairment joined the 150 healthy participants. Comparisons in the Clinical Dementia Rating (CDR) tiers tested the discriminability of the tests for different cognitive levels. The area under the receiver operating characteristic curve (AUROC) analyzed the power of ADAS-cog in predicting CDR 0.5 from CDR 0. RESULTS: The Taiwan version of ADAS-cog had fair reliability between items (α = 0.727) and good correlations to MMSE (r = -0.673, p < 0.001) and MoCA (r = -0.746, p < 0.001). The normative data of MMSE, MoCA, and ADAS-cog showed ladder changes with age (p = 0.006, 0.001, and 0.437) and education (p < 0.001, <0.001, and <0.001) in the 150 nondemented older adults. Next, in the 170 mixed participants from the communities and the hospital, MMSE, MoCA, and ADAS-cog scores were well differentiable between CDR 0, 0.5, and 1. In addition, ADAS-cog discriminated CDR 0.5 from 0 by an AUROC of 0.827 (p < 0.001). DISCUSSION/CONCLUSION: The three structured cognitive tests consistently reflect cognitive levels of healthy older adults. The Taiwan version of ADAS-cog is compatible with MMSE and MoCA to distinguish people with mildly impaired from normal cognition. In addition, this study derived MMSE, MoCA, and ADAS-cog norms tailored to demographic factors. The findings highlight the need for stratification of age and education rather than applying a fixed cutoff for defining normal and abnormal cognition.

PLCO: Evolution of an Epidemiologic Resource and Opportunities for Future Studies.

The Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO), a large-scale, multi-institutional, randomized controlled trial, was launched in 1992 to evaluate the effectiveness of screening modalities for prostate, lung, colorectal, and ovarian cancer. However, PLCO was additionally designed to serve as an epidemiologic resource and the National Cancer Institute has invested substantial resources over the years to accomplish this goal. In this report, we provide a summary of changes to PLCO's follow-up after conclusion of the screening phase of the trial and highlight recent data and biospecimen collections, including ancillary studies, geocoding, administration of a new medication use questionnaire, consent for linkage to Medicare, and additional tissue collection that enhance the richness of the PLCO resource and provide further opportunities for scientific investigation into the prevention, early detection, etiology and treatment of cancer.

Whole blood cryopreservation in epidemiological studies.

Standardized and cost-effective biological sample collection, processing, and storage procedures are needed in large-scale epidemiological studies to provide material for testing a broad range of etiological hypotheses. One component of sample collection in the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial involves shipment of blood in acid-citrate-dextrose anticoagulant to a central processing laboratory, where 10% DMSO is added, and whole blood aliquots are cryopreserved. A single technician is able to routinely process 50-60 samples/day. Tests conducted to evaluate potential uses of cryopreserved whole blood showed successful EBV transformation (>90%, up to 20 months of storage). In addition, lymphocytes maintained good viability and stable T-cell:B-cell ratios, and T cells maintained the capacity to proliferate in response to solid phase anti-CD3/CD28 plus interleukin 2. Whole blood cryopreservation is a cost-effective approach to large-scale storage of viable cells in epidemiological studies.