Received: 21 June 2018
Accepted: 16 January 2019
First Online: 1 February 2019
Ethics approval and consent to participate
: The survey was ethically audited and approved by the ethical commission of the Ministry of Education of Lower Saxony. This constitutes the state’s educational authority. The survey was strictly anonymized – no names, no addresses, and no school addresses were obtained. The parents of the respondents received information about the study in advance with a request that they grant written consent for their child to participate. The material we presented to them was a one-page information letter. Written consent was obtained from the parents respectively the legal representative of all participating adolescents. If the parent(s) respectively the legal representative did not give their consent, the student could not participate in the survey. The students were also allowed to refuse to participate in the survey, regardless of their parents’ respectively the legal representatives’ consent. The students were first reminded that the survey was voluntary, that there would be no negative consequences for refusing to participate, and that they had the right not to answer any of the questions.
: Not applicable.
: The authors declare that they have no competing interests.
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