Stage-Based Model

A model of personal-informatics use, introduced by Ian Li, Anind Dey, and Jodi Forlizzi (2010), describing how people move through five stages of self-tracking: preparation (deciding to track), collection, integration, reflection, and action. The model made early contributions to HCI research on self-tracking apps and devices and framed many subsequent studies. For accessibility, the model is useful for locating where a particular user or population struggles (e.g., neurodivergent users may stall at reflection, not collection); critics including Rudberg Selin et al. (2026) and Thudt et al. note that treating reflection as a subsequent step to collection underplays how reflection happens throughout the tracking process and across social contexts.