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.
Trajectories of cigarette smoking. Note: The points represent calculated average cigarette smoking scores for participants at a fixed age within one trajectory group. The large deviation of the observed points from the fitted values for the late onset intermittent, then cessation group is a result of small sample sizes at ages 49 and above that produce low precision of estimation.
