Recently, games have gained much momentum as enablers of health behavior change. Current projects
on health games, however, face a serious challenge: evaluation methods used to assess and formatively
evaluate such games do not adequately gauge acceptability and integration of the game into participants’
lives. These are crucial elements to enable adherence of the participants to the game to induce behavior
change. In this paper we present a formative evaluation methodology we developed, called Data-Driven
Retrospective Interviewing (DDRI). Used within naturalistic settings, DDRI investigates how participants
accept and integrate a game into their lives. The method is comprised of several steps. A game is first
instrumented to collect behavioral data, which is then analyzed to inform the construction of interview
questions used to retrospectively contextualize and reflect on participants’ behaviors. The contribution of
this paper is: the methodology and its application to evaluate a pervasive health game called SpaPlay (Seif
El-Nasr et al., 2011). Findings of this investigation helped designers re-think and augment their design as
they uncovered how users used their game, which, in some cases, was different from how they initially
intended. Such findings would have not been possible using conventional evaluation methods