Dataset Information

Underdiagnosis of mild cognitive impairment: A consequence of ignoring practice effects.

ABSTRACT:

Introduction

Longitudinal testing is necessary to accurately measure cognitive change. However, repeated testing is susceptible to practice effects, which may obscure true cognitive decline and delay detection of mild cognitive impairment (MCI).

Methods

We retested 995 late-middle-aged men in a ?6-year follow-up of the Vietnam Era Twin Study of Aging. In addition, 170 age-matched replacements were tested for the first time at study wave 2. Group differences were used to calculate practice effects after controlling for attrition effects. MCI diagnoses were generated from practice-adjusted scores.

Results

There were significant practice effects on most cognitive domains. Conversion to MCI doubled after correcting for practice effects, from 4.5% to 9%. Importantly, practice effects were present although there were declines in uncorrected scores.

Discussion

Accounting for practice effects is critical to early detection of MCI. Declines, when lower than expected, can still indicate practice effects. Replacement participants are needed for accurately assessing disease progression.

SUBMITTER: Elman JA

PROVIDER: S-EPMC6039708 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Publications

Underdiagnosis of mild cognitive impairment: A consequence of ignoring practice effects.

Elman Jeremy A JA Jak Amy J AJ Panizzon Matthew S MS Tu Xin M XM Chen Tian T Reynolds Chandra A CA Gustavson Daniel E DE Franz Carol E CE Hatton Sean N SN Jacobson Kristen C KC Toomey Rosemary R McKenzie Ruth R Xian Hong H Lyons Michael J MJ Kremen William S WS

Alzheimer's & dementia (Amsterdam, Netherlands) 20180514

<h4>Introduction</h4>Longitudinal testing is necessary to accurately measure cognitive change. However, repeated testing is susceptible to practice effects, which may obscure true cognitive decline and delay detection of mild cognitive impairment (MCI).<h4>Methods</h4>We retested 995 late-middle-aged men in a ∼6-year follow-up of the Vietnam Era Twin Study of Aging. In addition, 170 age-matched replacements were tested for the first time at study wave 2. Group differences were used to calculate ...[more]

PMID: 30003138

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Dataset Information

Underdiagnosis of mild cognitive impairment: A consequence of ignoring practice effects.

Introduction

Methods

Results

Discussion

Publications

Underdiagnosis of mild cognitive impairment: A consequence of ignoring practice effects.

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