DOI: 10.3886/icpsr36053.v1
title: Cognition and Aging in the USA (CogUSA) 2007-2009
title: Version 1

description: Cognition and Aging in the USA (CogUSA) is a national longitudinal study of cognition, focused on the age-related changes in cognition across cohorts and on the impact of cognition on key health and economic outcomes. The aim of the CogUSA Study was to evaluate the effectiveness of a variety of tests in assessing cognitive skills on a sample mirroring the Health and Retirement Survey (HRS) (ICPSR 6854). Data were derived in three waves, with each wave utilizing a variety of measures. In Waves 1 and 3, these measures included an adaptive number series test. The Woodcock-Johnson (WJ-III) number series test and the Wechsler Abbreviated Scale of Intelligence (WASI) were used in Wave 2. Waves 1 and 3 were conducted as telephone interviews, while Wave 2 was conducted as an in-person interview. This collection includes indicators of cognitive abilities and functioning as well as a variety of demographic, health, and economic variables. Dataset 1 presents participant demographic information, and Dataset 2 presents scores calculated for the cognitive tests administered to the respondents in each of the three waves.
description: The goals of CogUSA were: (1) to develop efficient methods of assessing well-recognized components of intelligence and personality that can be administered by surveys using either face-to-face or telephone administration; and (2) to collect multivariate information to better understand how various cognitive abilities change with age.
description: The CogUSA Study consists of three survey components. Initial contact was established by telephone calls to selected households, and the study began with a 40-minute telephone interview (Wave 1) that replicated the sections of the HRS questionnaire on demography, health and cognition, and added a few brief cognitive tests. This Wave 1 telephone survey was followed as quickly as possible - ideally, within a week - by a 3 hour face-to-face cognitive assessment (Wave 2) of the cognitive abilities of respondents on a large number of different tasks measuring components of "fluid and crystallized intelligence" (after Horn and McArdle, 2007). Respondents were paid $20 for participation in the Wave 1 interview and $60 for the longer Wave 2 interview. Data collection for Wave 1 took place between May and December, 2007. A second telephone survey (Wave 3) took place at a randomized interval of 1 to 24 months following the personal interview (following the Timelag strategy of McArdle and Woodcock, 1997). Randomizations for the Wave 3 telephone interview were done at the respondent, not household, level. Respondents were randomly assigned to one of eight follow-up target dates. Wave 3 telephone interviews began in February, 2008 and continued through September, 2009.
description: The data are not weighted. However, Dataset 1 includes the weight variable COGWT, which is a respondent-level sample weight based on Wave 2. For more information on weights, please refer to the document entitled "Original P.I. Documentation."
description: Response Rates: 47 percent; for more information on response rates across the three waves, please refer to the document entitled "Original P.I. Documentation."
description: Presence of Common Scales: Woodcock-Johnson III (WJ-III; Woodcock, McGrew, and Mather, 2001; Woodcock and Mather, 2001) Wechsler Abbreviated Scale of Intelligence (WASI; Wechsler, 1999) Big Five Inventory (BFI; John and Srivastava, 1999)
description: The study employs a two-stage RDD sample supplemented with information from a Genesys database to target a sample of households with individuals located in 28 primary sampling units (PSUs) across the nation. Eligible sample members included individuals born in 1956 or earlier and their significant others, regardless of age.
description: Datasets: DS0: Study-Level Files DS1: Demographic Data DS2: Test Score Data
description: Individuals living in the United States, born in 1956 or earlier and their significant others, regardless of age. Smallest Geographic Unit: Census Region
description: cognitive assessment test; face-to-face interview; telephone interviewThis study is closely related to the Health and Retirement Study (HRS) (ICPSR 6854). Please refer to the file entitled "Original P.I. Documentation" for more details.The two datasets in this collection can be linked using the variable SAMPID.