. 2013 Jan 28;2(1):e7. doi: 10.2196/resprot.2410
©Kirsti Riiser, Knut Løndal, Yngvar Ommundsen, Turid Sundar, Sølvi Helseth. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 28.01.2013.
This is an open-access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work, first published in JMIR Research Protocols, is properly cited. The complete bibliographic information, a link to the original publication on http://www.researchprotocols.org, as well as this copyright and license information must be included.