Figure 1.
The Evaluating the Efficacy of E-Cigarette (E3) use for Smoking Cessation trial flow chart.
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.