Addressing engagement in technology-based behavioural HIV interventions through paradata metrics.

<p><b>PURPOSE OF REVIEW: </b>The goal of this review was to examine how often researchers report participants' online engagement using paradata (i.e. intervention usage metrics) when describing the outcomes of online behavioural HIV prevention and care interventions. We also highlight the utility of paradata collection and analysis in future technology-based trials.</p><p><b>RECENT FINDINGS: </b>We focused on studies indexed on PubMed and published between 1 January 2016 and 31 March 2017 that reported the development and testing of online behavioural interventions for HIV prevention and/or care. Of the 705 extracted citations, six met study criteria.</p><p><b>SUMMARY: </b>Only one study reported paradata reflecting participants' engagement with a technology-based intervention. Researchers should systematically collect and analyse paradata to strengthen the evidence base for technology-based interventions (do they work?), advance the use of behaviour change theory across modalities and platforms (how/why do they work?) and inform reach and scale-up efforts (for whom do they work?). Researchers may also rely on paradata to examine dose-response relationships due to user engagement, to identify replicable core components linked to behaviour change outcomes, to allocate resources judiciously and drive down development costs, and to pool these metrics for use in future meta-analyses.</p>