National Health and Nutrition Examination Survey (NHANES)

Data from Cognitive Performance and Subjective Cognitive Decline

NHANES is designed to assess the health and nutritional status of adults and children in the United States. Conducted since 1960, the survey includes both interview and physical examination components. The survey examines a nationally representative sample of about 5,000 people each year. The NHANES interview includes demographic, socioeconomic, dietary, and health-related questions. The examination component consists of medical, dental, and physiological measurements, as well as laboratory tests administered by highly trained medical personnel.

NHANES 2011–2012 and 2013–2014

Data on cognitive performance in adults aged 60 years and older were collected from 2011–2014. Assessments conducted included:

Subjective Cognitive Decline
10-item word list learning with both immediate and delayed recall
Animal Fluency
Digit Symbol Substitution

In the home interview, a self-rated question on subjective cognitive decline (SCD question) was asked:

“During the past 12 months, have you experienced confusion or memory loss that is happening more often or is getting worse?” Response categories were yes or no.

The SCD question is part of the optional cognitive decline module from the BRFSS, developed to determine the need for public health activities among adults residing in the community

The Consortium to Establish a Registry for Alzheimer’s Diseaseexternal iconexternal icon(CERAD) provides a test that measures immediate and delayed memory. A participant reads a 10-item word list (CERAD-WL) and is asked to immediately recall those 10 items. Later, after completion of the Animal Fluency and Digit Symbol Substitution tasks, the participant is asked to again list those same 10 items as a delayed recall (CERAD-DR).

The Animal Fluency test measures verbal fluency and asks participants to name as many animals as possible in 1 minute.

The Digit Symbol Substitution Test askes participants to match symbols to a corresponding number during a timed test as a measure of attention and processing speed.

NHANES cognitive performance data are publicly accessible and available at the NHANES website. All data for cognitive performance can be found under Questionnaire Data. SCD data are in the Medical Conditions data file, and data for the cognitive functioning assessments are in the Cognitive Functioning data file.

For an example of an analysis conducted using these data and a more detailed description of NHANES and the cognitive variables, please refer to this article pdf iconpdf icon[PDF-659 KB].

NHANES 2019–2020

Data on cognitive performance in adults aged 60 years and older were collected from 2019–2020. Assessments conducted included:

Subjective Cognitive Decline

Montreal Cognitive Assessment (MoCA)

In the home interview, a self-rated question on subjective cognitive decline (SCD question) was asked:

“During the past 12 months, have you experienced confusion or memory loss that is happening more often or is getting worse?” Response categories were yes or no.

The SCD question is part of the optional cognitive decline module from the BRFSS, developed to determine the need for public health activities among adults residing in the community

The Montreal Cognitive Assessment (MoCA) is a widely used measure for accurately detecting levels of cognitive decline. The assessments in the test attempt to gauge areas of language, visuospatial abilities, memory and recall and abstract thinking, to give a representation of a person’s current cognitive ability. This cognitive functioning task pdf iconpdf icon[PDF-27.7 KB] is administered to adults aged 60 years and older during the NHANES physical exam component.

Any future data releases will be posted on this page.

Page last reviewed: August 27, 2020

Content source: Division of Population Health, National Center for Chronic Disease Prevention and Health Promotion