Received: 25 September 2018
Accepted: 8 February 2019
First Online: 22 February 2019
Ethics approval and consent to participate
: The study was approved by the Juntendo University Ethical Committee, Japan, with approval number 2012194, and the Institutional Review Board at Boromarajonani College of Nursing, Lampang, Thailand, with approval number E2556/005. It was registered as an international current control trial at the ISRCTN registry. The ISRCTN registration number ISRCTN89315117 was assigned on 9th July 2013 [CitationRef removed]. Written consent was obtained from each of the participants after a thorough explanation was given about what would happen to them during the study, as well as their autonomous decision to give up smoking.
: Written informed consent for publication was obtained to publish the findings.
: The authors declare that they have no competing interests.
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