Table 3. Predicted Population Changes in Quit Attempts and Intentions to Quit Among Baseline Smokers and Sustained Quits Among Quitters at First Follow-up, Evaluation of the National Tips From Former Smokers Campaign, 2014–2015.

Population Outcome	Valuea
Incidence of past 3-month quit attempt, %
At baseline	37.5 (36.8–38.2)
At follow-up	41.9 (41.2–42.7)
Increase in population level quit attempts attributable to campaign, in millions, n	1.83 (1.81–1.85)
Sustained quit rate among people who attempt to quitb, %	5.7 (3.9–8.2)
Sustained quits attributable to campaign, in thousands, n	104 (103–106)
Incidence of 6-month intention to quit, %
At baseline	21.1 (20.7–21.6)
At follow-up	25.3 (24.8–25.9)
Population increase in smokers with intention to quit within 6 months, in millions, n	1.73 (1.70–1.77)

^a All parenthetical values are 95% confidence intervals.

^b Defined as sustaining nonsmoker status at each follow-up survey.