Reactivity to ecological momentary assessment: an example using undergraduate problem drinkers.

A. A. Stone and S. Shiffman (1994) defined ecological momentary assessment (EMA) as monitoring or sampling strategies that assess phenomena at the moment they occur in natural settings, thus maximizing ecological validity while avoiding retrospective recall. To address the extent to which EMA affects the behaviors and cognitions under observation, the authors examined behavioral and motivational reactivity to EMA among male and female undergraduate problem drinkers (n = 33). Participants completed a 2-week monitoring protocol using palmtop computers as well as pre- and postmonitoring measures of their drinking behavior and motivation for change. The findings suggest that the magnitude of reactivity to EMA is small. Suggestions for future research are presented.