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. 2005 Mar 31;7(1):e11. doi: 10.2196/jmir.7.1.e11

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© Gunther Eysenbach. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 31.3.2005. Except where otherwise noted, articles published in the Journal of Medical Internet Research are distributed under the terms of the Creative Commons Attribution License (http://www.creativecommons.org/licenses/by/2.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited, including full bibliographic details and the URL (see "please cite as" above), and this statement is included.

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An example for logarithmic “attrition curves” in a hypothetical eHealth trial. In the intervention group (INTV), a proportion of participants will be lost to follow-up (INTV dropout), as will be in the control group (CTRL dropout). In addition, even within those not lost to follow up, there might be a proportion of nonusers