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. 2018 Dec 18;20(12):e294. doi: 10.2196/jmir.9284

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©Karla Lancaster, Aseel Abuzour, Manmeet Khaira, Annalise Mathers, April Chan, Vivian Bui, Annie Lok, Lehana Thabane, Lisa Dolovich. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 18.12.2018.

This is an open-access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work, first published in the Journal of Medical Internet Research, is properly cited. The complete bibliographic information, a link to the original publication on http://www.jmir.org/, as well as this copyright and license information must be included.

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Summary chart of risk of bias assessment for included studies. Risk of bias summary: Green "+" symbols indicate a low risk of bias, yellow "?" symbols indicate an unknown risk of bias, and red "-" symbols indicate a high risk of bias.