Published on in Vol 5, No 1 (2020): Jan-Dec
Preprints (earlier versions) of this paper are
available at
https://preprints.jmir.org/preprint/18649, first published
.
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1 School of Mathematical & Computer Sciences, Heriot-Watt University, Edinburgh, United Kingdom
2 The Open University, Milton Keynes, United Kingdom
*all authors contributed equally