Table 3.

Quitting and switching cigarette use during follow-up

	Cigarette use at baseline
	E-cigarettes only	Tobacco cigarettes only	Dual use
	(n=229)	(n=480)	(n=223)
Switching to another product use group at 24 months	(n=229)	(n=480)	(n=223)
No switch	42.4	75.6	16.6
Switch to no product use	18.8	17.5	14.3
Switch from e-cigarettes only to dual use or tobacco-only smoking	38.9	–	–
Switch from dual use or tobacco-only smoking to e-cigarettes only	–	5.6	11.7
Switch from dual use to tobacco-only smoking	–	–	57.4
Switch from tobacco only to dual use	–	1.3	–
Quitting all product use
Quit all product use* at 12 months (n=125)	(n=34)	(n=65)	(n=26)
Remained abstinent from both tobacco cigarettes and e-cigarettes at 24 months	76.5	72.3	69.2
Relapsed to either tobacco and/or e-cigarettes at 24 months	23.5	27.7	30.8
Tobacco smoking quitters at 12 months (n=106)	(n=0)	(n=69)	(n=37)
Remained abstinent from smoking at 24 months	–	69.7	74.0
Relapsed to tobacco smoking at 24 months	–	30.3	26.0

*Both tobacco smoking abstinence/cessation and e-cigarette use abstinence/cessation.