Orbell, S., Hodgkins, S., & Sheeran, P. (1997). Implementation intentions and the theory of planned behavior. Personality and Social Psychology Bulletin, 23, 945-954.

Examines the implications of P. Gollwitzer's (1993) concept of implementation intentions (IMIs) for the theory of planned behavior (e.g., I. Ajzen, 1995), in 155 female students and staff. Attitude, subjective norm, perceived behavioral control, and intentions were assessed before an intervention that required Ss to make IMIs concerning when and where they would perform breast self-examination during the next month. Behavior was assessed by self-report 1 mo later. Results supported Gollwitzer's contention that goal intentions that have been supplemented by IMIs, concerning where and when the behavior is to be performed, are more likely to be enacted. Evidence suggested that IMIs were effective because they provided a mechanism that facilitated the retrieval of intentions in memory. IMIs also reduced the capacity of past behavior to predict future behavior, suggesting that IMIs mimic the effect of habit in human action. ((c) 1997 APA/PsycINFO, all rights reserved).