1. Summary of proportion of participants abstinent from smoking at 6+ months follow‐up: cohort studies of nicotine EC.

Study	Motivated or unmotivated to quit smoking?	% abstinent
Cohort studies		6‐month	12‐month	18‐month	24‐month	Notes
Adriaens 2014a	Unmotivated to quit	19.6% (10/51)	‐	‐	‐	Data from 8‐month follow‐up
Bell 2017	"Willing to attempt to quit"	26.6% (8/30)	‐	‐	‐	‐
Caponnetto 2013b	Unmotivated to quit	‐	14% (2/14)	‐	‐	‐
Ely 2013b	Motivated to quit	44% (21/48)	‐	‐	‐	‐
Pacifici 2015	Unmotivated to quit	‐	53% (18/34)	‐	‐	‐
Polosa 2011	Unmotivated to quit	23% (9/40)	‐	15% (6/40)	13% (5/40)	‐
Polosa 2014b	Unmotivated to quit	36% (18/50)	‐	‐	‐	‐
Polosa 2015	Not defined	42% (30/71)	41% (29/71)	‐	‐	‐

^aTechnically an RCT but observational for purposes of EC analysis.
^bAll participants (N = 48) used an EC, but 16 also used bupropion and 2 used varenicline.