Methods summary.

<p>The study is based on the method used by Ong et al. that builds on existing LCA data for end-point devices used in videoconferencing and emission estimates for Internet traffic <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0105040#pone.0105040-Ong1" target="_blank">[17]</a>. Completeness of the LCA data varies between devices, but includes energy costs and/or carbon emissions generated during manufacturing (M), distribution (D), operation (O) and end-of-life stages (E). Emissions data for MDE are provided in, or has been converted to, energy equivalents (kWh/unit) and is called embodied energy. Data for the videoconferencing solution (monitors, camera and video codecs) were modified to better fit our technological set-up. To obtain the hourly carbon cost of telerehabilitation in kgCO₂e, we divided the embodied energy with estimates of the life length and use rates of all equipment, and applied a conversion factor of 0.6 kg CO₂e/kWh <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0105040#pone.0105040-Ong1" target="_blank">[17]</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0105040#pone.0105040-Malmodin1" target="_blank">[20]</a>. See also <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0105040#pone.0105040.e001" target="_blank">Equation 1</a>.