Slow, slow, quick, quick, slow: the shifting dynamics of five altmetric sources observed over a decade

The attention surrounding research outputs, as partially captured by altmetrics, or alternative metrics, constitutes many varied forms of data. Each of these presents their own activity profile: varying by discipline, by year of publication and by time since published. Some attention accrues through activities that take a moment’s consideration; other attention sources take months or years of consideration and curation before being realized. These differences need to be accommodated by altmetric users. The study of temporal trends in altmetrics is under-developed, and this multi-year observation study addresses some of the deficits in our understanding of altmetric behaviour over time and the history of its development. From a set of 7739 papers sampled over the period 2008-2021 the growth of Mendeley and Twitter is confirmed, alongside an apparent decline in blogging attention. The Open Access Altmetric Advantage is seen to emerge and evolve over time, with each attention source showing different trends. The existence of late-emergent attention in all attention sources is confirmed. Policy attention is identified as the slowest form of impact studied by altmetrics, and one that strongly favours the Humanities and Social Sciences.