DOI: 10.3886/icpsr25281.v7
title: Midlife in the United States (MIDUS 2): Cognitive Project, 2004-2006
title: Version 7

description: In 1994/1995, the MacArthur Midlife Research Network carried out a national survey of over 7,000 Americans aged 25 to 74. The purpose of the study was to investigate the role of behavioral, psychological, and social factors in understanding age-related differences in physical and mental health. A description of the study and findings from it are available at the MIDUS website.
With support from the National Institute on Aging, a longitudinal follow-up of the original MIDUS samples (core sample (N = 3,487), metropolitan over-samples (N = 757), twins (N = 957 pairs), and siblings (N = 950)) was conducted in 2004-2006. Guiding hypotheses, at the most general level, were that behavioral and psychosocial factors are consequential for health (physical and mental). The purpose of the Cognitive Project was to determine how cognition is related to overall mental and physical health. Specific goals were: (1) to characterize the nature and range of midlife cognitive performance, relative to those younger and older, across multiple domains in a nationally representative sample (MIDUS); and (2) to examine the relationship between biopsychosocial factors (e.g., SES, health status, health-promoting behaviors, metabolic and cardiovascular biomarkers, depression, personality, control beliefs, stressful life events) and individual differences in cognitive functioning. 
The development of a cognitive battery for the second wave of testing of the Midlife Development in the United States (MIDUS) study provided an opportunity to examine the cognitive performance of young, middle-aged and older adults from a wide range of education levels in a large-scale, national sample. As part of the Cognitive Project of the MIDUS II the Brief Test of Adult Cognition by Telephone (BTACT) (Lachman & Tun, 2008; Tun & Lachman, 2006) was administered. More information about the BTACT can be found at the Brandeis website.
The BTACT represents the first comprehensive cognitive battery, including measures of speed and reaction time, to be administered by telephone to a national sample across the adult years and into later life. With a response rate of over 86 percent for the cognitive testing component of the MIDUS II, a cognitive data set of unprecedented range in terms of age, gender, socioeconomic status (SES), education, and geographic diversity was produced.
description: Response Rates: Completion rates (the denominator is the number of cases successfully completing the initial phone survey) for the cognitive assessments were: Main RDD -- 85 percent, Sibling -- 92 percent, Twin -- 87 percent, and Milwaukee -- 52 percent.
description: Presence of Common Scales: Rey Auditory-Verbal Learning Test
WAIS-III (backward digit span test)
Verbal Fluency-Animal Category
Attention-Task Switching/Reaction Time Tests
Inductive Reasoning Speed of Processing Tests
description: All respondents participating in MIDUS 2 (the longitudinal follow-up to MIDUS 1 (ICPSR 2760) or the MIDUS 2 Milwaukee study (ICPSR 22840) were eligible to participate in the cognitive assessments.
description: Datasets: 
DS1: Midlife in the United States (MIDUS 2): Cognitive Project, 2004-2006
description: Adult noninstitutionalized population in the contiguous United States. Smallest Geographic Unit: No geographic information is included other than for the Milwaukee cases.
description: computer-assisted telephone interview (CATI); cognitive assessment testAll data files in the MIDUS study (both longitudinal and cross-sectional) can be linked using a key variable called M2ID.The DDI codebook (PDF file) released by ICPSR was provided by MIDUS and was not changed in any way by ICPSR. This original file does not reflect any of the curation done by ICPSR.The title of this study was changed from National Survey of Midlife Development in the United States (MIDUS II): Cognitive Project, 2004-2006, to Midlife in the United States (MIDUS 2): Cognitive Project, 2004-2006, on May 12, 2017.Additional information about the Midlife Development in the United States study can be found at the
MIDUS website.