Visitors   Views   Downloads
NOT PEER-REVIEWED
"PeerJ Preprints" is a venue for early communication or feedback before peer review. Data may be preliminary.

A peer-reviewed article of this Preprint also exists.

View peer-reviewed version

Additional Information

Competing Interests

The authors declare they have no competing interests.

Author Contributions

Gerrit Hirschfeld conceived and designed the experiments, performed the experiments, analyzed the data, contributed reagents/materials/analysis tools, wrote the paper, prepared figures and/or tables, reviewed drafts of the paper.

Julia Wager conceived and designed the experiments, performed the experiments, reviewed drafts of the paper.

Boris Zernikow conceived and designed the experiments, analyzed the data, reviewed drafts of the paper.

Human Ethics

The following information was supplied relating to ethical approvals (i.e., approving body and any reference numbers):

In this study the following data was used: Public Use File KiGGS, The German Health Survey for Children and Adolescents 2003-2006, Robert Koch Institute, Berlin (Germany), 2008. The design and ethics of which are referenced in the manuscript.

Funding

The authors declare there was no funding for this work. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.


Add your feedback

Before adding feedback, consider if it can be asked as a question instead, and if so then use the Question tab. Pointing out typos is fine, but authors are encouraged to accept only substantially helpful feedback.

Some Markdown syntax is allowed: _italic_ **bold** ^superscript^ ~subscript~ %%blockquote%% [link text](link URL)
 
By posting this you agree to PeerJ's commenting policies