The life cycle of altmetric impact: A longitudinal study of six metrics from PlumX

The main objective of this study is to describe the life cycle of altmetric and bibliometric indicators in a sample of publications. Altmetrics (Downloads, Views, Readers, Tweets, and Blog mentions) and bibliometric counts (Citations) (in this study, the indicators will be capitalized to differentiate them from the general language) of 5185 publications (19,186 observations) were extracted from PlumX to observe their distribution according to the publication age. Correlations between these metrics were calculated from month to month to observe the evolution of these relationships. The results showed that mention metrics (Tweets and Blog mentions) are the earliest metrics that become available most quickly and have the shortest life cycle. Next, Readers are the metrics with the highest prevalence and with the second fastest growth. Views and Downloads show a continuous growth, being the indicators with the longest life cycles. Finally, Citations are the slowest indicators and have a low prevalence. Correlations show a strong relationship between mention metrics and Readers and Downloads, and between Readers and Citations. These results enable us to create a schematic diagram of the relationships between these metrics from a longitudinal view.