When a Plan Comes Together
The theory of planned behaviour is a model that tries to predict human behaviour. As noted by the author, Icek Azjen, explaining behaviour is a difficult task due to the many complex psychological variables that must be taken into account. The theory of planned behaviour is a relatively simple and accurate model and it is mainly for these reasons it has garnered a lot of attention among researchers. Even for those of us who had not heard of this theory beforehand it continues to be a relevant part of our lives since it is used to predict our behaviour towards many social projects (such as our intention to donate blood).
As you can see, the model looks fairly simplistic, but the jargon can get in the way of our understanding. Let’s break it down:
Behaviour and Intention are fairly straight forward; behaviour is the action we take and our intention is our plan or motivation to commit to that action. Keep in mind that intention does not always lead to behaviour – but studies have shown that expressing that intent multiple times leads to an increased chance of taking action (Cooke & Sheeran, 2004). So the question is what determines our intentions. In this model the predictors of Intention are Attitudes, Subjective Norms and Perceived Behavioural Control (PBC).
- Attitude (toward the behaviour) is our perception on whether the act is favourable. For example, if we believe exercise is good for our health then that can lead to an intention to start or increase our exercise regime.
- Subjective Norm refers to the degree to which important people in our lives condone a certain act. This means our family, friends and colleagues can have an impact on our intentions depending on their beliefs.
- Perceived Behavioural Control is a person’s perception that they can engage in an action successfully. Put simply, if we believe we can perform a task with the resources we have at hand then we are more likely to engage in that task. PCB can also prevent us from taking an action if we believe the resources are not enough (such as time constraints). The best example I can think of is studying; if we believe we are knowledgeable and disciplined with enough time to complete our assignment then we are more likely to have intent to begin the work. Perhaps the most interesting part of PCB is that we do not necessarily need intent to do something in order to engage in an action (behaviour). This occurs when we are oblivious to factors that facilitate or obstruct our intended behaviour.
So what do you think of Azjen’s theory of planned behaviour? Can you think of examples in your own life that support (or perhaps go against) the theory?
Cooke, R., & Sheeran, P. (2004). Moderation of cognition-intention and cognition-behaviour relations: A meta-analysis of properties of variables from the theory of planned behaviour. British Journal of Social Psychology, 43, 159-186.