Minute level step counts and physical activity data from the National Health and Nutrition Examination Survey (NHANES) 2011-2014

The National Health and Nutrition Examination Survey (NHANES) is a nationally
representative study that collects demographic, socioeconomic, dietary, and
health-related information from 10,000 Americans annually. In Wave G
(2011-2012) and Wave H (2013-2014), participants wore an ActiGraph GT3X+ on
the non-dominant wrist for seven consecutive days. Publicly available data
include minute-level wear predictions (wake wear, sleep wear, unknown,
nonwear), data quality flags, and monitor-independent movement summary units
(MIMS). Additionally, raw triaxial accelerometer data recorded at 80 Hz are
provided, enabling detailed analyses beyond MIMS.

We applied five step counting algorithms and the ActiGraph Activity Count (AC)
algorithm to the raw data to create a dataset of minute-level step counts. The
dataset also includes minute level AC, MIMS, wear predictions, and wear flags
for all participants who wore accelerometers in NHANES 2011-2014\. These data
facilitate detailed investigations of accelerometry-measured physical activity
patterns in a nationally representative U.S. population. Potential analyses
include examination of within-day activity patterns and their association with
health outcomes.