Idehen, Esther E.
Koponen, Päivikki
Härkänen, Tommi
Kangasniemi, Mari
Pietilä, Anna-Maija
Korhonen, Tellervo
Article History
Received: 9 November 2017
Accepted: 26 April 2018
First Online: 4 May 2018
Ethics approval and consent to participate
: For both sets of data (the Maamu study; 325/13/03/00/2009, and the Health 2011 survey 45/13/03/00/11), the coordinating ethics committee of the Hospital District of Helsinki and Uusimaa in Finland granted ethics approval. Each participant gave a written informed consent before the interview.
: TK declares no competing interest concerning this work, but she reports having served as an occasional consultant 2012–2016 to Pfizer, a pharmaceutical company involved in nicotine dependence treatment. Other authors declare that they have no competing interests.
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