Funding for this research was provided by:
The Ministry of Social Affairs and Health, Helsinki, Finland (based on the article 52 Appropriation of the Lotteries Act).
Text and Data Mining valid from 2018-06-05
Received: 28 June 2017
Accepted: 25 May 2018
First Online: 5 June 2018
Ethics approval and consent to participate
: The survey was conducted in accordance with the ethical standards of the Declaration of Helsinki. The Ethics Committee of the National Institute for Health and Welfare, Finland, approved the research protocol (THL/1122/6.02.01/2014). Potential participants received written and verbal information about the study and the principles of voluntary participation. Verbal informed consent was obtained from all participants. Permission to use the register data was obtained from Statistics Finland.
: The authors do not hold any position, receive ongoing or significant funding, and are not engaged in any business or with any organization that creates a real or perceived conflict of interest in their work on this manuscript.
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