Reasons for Electronic Nicotine Delivery System use and smoking abstinence at 6 months: a descriptive study of callers to employer and health plan-sponsored quitlines.

ENDS users not using ENDS to quit smoking were less successful at quitting at 6-month follow-up compared with callers using ENDS to quit smoking and callers who did not use ENDS at programme registration. Incorporating reasons for ENDS use may be important for future studies examining the role of ENDS in tobacco cessation.