• Relatively simple basis for identifying where and how to target change
    • Well-supported in the literature
    • Includes social norms, a construct not provided in other theories


    • TRA on its own, is not sufficient to predict behaviors in which volitional control is limited.
    • The role of past behavior.
      • According to the assumptions of the model, effects of external variables, such as past behavior, on intention and behavior should be mediated by the TRA / TPB constructs [1] However, a number of studies have shown that there is a residual effect of past behavior on the target behavior [2-4].
      • A meta-analysis of studies applying TRA / TPB to condom use found intention and perceived behavioral control to be more strongly associated with past behavior than with future behavior.
        • This pattern suggests that although intentions influence future behavior, individuals' past behavior can influence their intentions [5].
        • It is important to consider how researchers measure behavior in studies applying TRA / TPB, IBM, e.g. are behaviors being measured as predictive or postdictive?

1. Ajzen, I. (1991). The theory of planned behavior. Organizational Behavior and Human Decision Processes, 50, 179211.

2. Reinecke, J., Schmidt, P., & Ajzen, I. (1996). Application of the theory of planned behavior to adolescents' condom use: A panel study. Journal of Applied Social Psychology, 16, 749772.

3. Rhodes, R.E., & Courneya, K.S. (2003). Modelling the theory of planned behaviour and past behaviour. Psychology. Health and Medicine, 8, 5768.

4. Yzer, M., Capella, J.N., Fishbein, M., & Hornik, R. (2004). The role of distal variable in behaviour change: Effects of adolescents' risk for marijuana use on intention to use marijuana. Journal of Applied Social Psychology, 34, 12291250.

5. Albarracin, D., Fishbein, M., Johnson, B.T., & Muellerleile, P. (2001). Theories of reasoned action and planned behavior as models of condom use: A meta analysis. Psychological Bulletin, 123, 142161.