Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Recorded (black dots) and self-reported (gray bars) duration of active use in n=29 participants; * denotes participants who did not consent to or failed in the retrieval of tracker data; ^ denotes participants who declined to interview. NSC: national steps challenge.
