Received: 8 March 2018
Accepted: 8 June 2018
First Online: 25 June 2018
Ethics approval and consent to participate
: This study was approved by the Sheba Hospital Ethical Committee. All participants provided written informed consent. Researchers analysing urinary cotinine levels and conducting data analysis had no access to identifying details of study participants.
: Not applicable.
: The authors declare that they have no competing interests.
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