The Effects of Outcome Expectations and Satisfaction on Weight Loss and Maintenance: Correlational and Experimental Analyses— A Randomized Trial Emily A. Finch, Jennifer A. Linde, Robert W. Jeffery, Alexander J. Rothman, and Christie M. King University of Minnesota, Twin Cities Rona L. Levy University of Washington This study examines the hypothesis that highly favorable outcome expectations promote weight loss and hinder weight maintenance. To investigate the effects of outcome expectations and satisfaction with treatment outcomes on weight loss, 349 adults were randomly assigned to 1 of 2 weight loss programs that emphasize either (a) an “optimistic” message, focusing exclusively on the positive aspects of weight loss, or (b) a “balanced” message, giving equal time to positive and negative aspects of weight loss. Participants changed their weight loss cognitions in response to the intervention, but there was no significant difference between the intervention treatment groups in short-term or long-term (18-month) weight loss. Independent of treatment message, positive outcome expectations and satisfaction were both associated with weight loss. Keywords: obesity, weight loss, outcome expectations, satisfaction, psychosocial factors Although progress in weight loss treatment over the last 20 years has resulted in significant improvements in the magnitude of initial weight losses, even the most promising methods continue to produce poor rates of maintained weight loss (Jeffery et al., 2000). The present study attempted to address this problem by developing and testing an intervention grounded in a new conceptual model of behavior change that differentiates between initiation and mainte- nance (Rothman, 2000). The model argues that expectancies about the process and outcomes associated with weight loss are impor- tant determinants of initial efforts in a weight loss program, whereas satisfaction with weight loss outcomes is a more impor- tant determinant of sustained weight loss. The study involved an experimental manipulation designed to elicit either an optimistic or a balanced view of the outcomes associated with weight loss efforts, and subsequently, the impact of experimentally induced expectancies on thoughts, feelings, and weight loss success. The Two-Criterion Approach to Behavior Change Given the difficulty people have maintaining weight loss, it seems reasonable to postulate that the decision criteria that guide initial efforts differ from those that guide sustaining those behav- iors. The theory guiding this research represents a shift from the view that behavioral maintenance is an extension of behavioral initiation to the perspective that the critical beliefs that underlie behavioral initiation and maintenance are different (Rothman, 2000; Rothman, Baldwin, & Hertel, 2004). Specifically, we be- lieve that positive expectations regarding the outcomes afforded by behavior change are the primary determinant of initiation of new behaviors such as those needed to lose weight. However, over time, satisfaction with the experienced outcomes associated with weight loss replace outcome expectations as the primary determi- nant of whether newly adopted behaviors are maintained. The premise that the tendency to adopt a behavior is a function of expectations regarding the consequences of the behavior is consistent with nearly all cognitive theories of behavior change that have been applied to the problem of weight loss (theory of reasoned action [Ajzen & Fishbein, 1980], self-determination the- ory [Deci & Ryan, 1985], social cognitive theory [Bandura, 1986], the health belief model [Rosenstock, Strecher, & Becker, 1988], the theory of planned behavior [Ajzen, 1991], and the transtheo- retical model of health behavior change [Prochaska, DiClemente, & Norcross, 1992]). Yet, despite its intuitive appeal, the premise that positive expectations about the outcomes of behavior change (e.g., improved health, attractiveness to others, ability to complete activities) predict weight loss has yet to be tested experimentally. Although we expect the initiation of weight loss behaviors should be responsive to outcome expectancies, we assert that the decision to sustain weight loss behavior is predicated on an overall evaluation of the favorable and unfavorable consequences of ef- forts and a determination of whether the actually experienced consequences are worth the effort (see Rothman, 2000, for more detail). There is some correlational evidence that satisfaction is associated with weight maintenance (Head & Brookhart, 1997; Emily A. Finch, Jennifer A. Linde, Robert W. Jeffery, and Christie M. King, Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Twin Cities Campus; Alexander J. Roth- man, Department of Psychology, University of Minnesota, Twin Cities Campus; Rona L. Levy, School of Social Work, University of Washington. This research was supported by National Institute of Neurological Disorders and Stroke Grant 1R01-NS38441. Correspondence concerning this article should be addressed to Robert W. Jeffery, Division of Epidemiology, School of Public Health, University of Minnesota, Twin Cities Campus, 1300 South Second Street, Suite 300, Minneapolis, MN 55454-1015. E-mail: jeffery@epi.umn.edu Health Psychology Copyright 2005 by the American Psychological Association 2005, Vol. 24, No. 6, 608 – 616 0278-6133/05/$12.00 DOI: 10.1037/0278-6133.24.6.608 608 This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly.