Theory of Planned Behavior
Instrumental to the field of school psychology, and subsequent theories of behavior change, is the Theory of Planned Behavior (TPB; Ajzen, 1991). The TPB was developed as an extension of the Theory of Rational Action (Ajzen & Fish-bein, 1977), both of which posit that individuals make logical and reasoned choices to engage in particular behaviors after evaluating information that is available to them (DiClemente, Salazar, & Crosby, 2013). The TPB is also a value-expectancy theory, in that it considers behavior change dependent on whether an individual perceives the benefits of changing a behavior as outweighing associated costs (DiClemente et al., 2013). Key to the TPB is the idea that behavior occurs based on a combination of three central facets: attitudes, subjective norms, and perceived behavioral control. Further, a foundational principle of the TPB is that intention is the most salient predictor of behavior (Ajzen, 1991). Within the context of an MI framework, a school psychologist may help a teacher or parent by asking provocative questions, demonstrating empathy, eliciting change talk, and ultimately helping to uncover intention. At a basic level, the TPB suggests that behavioral intention is a result of a combination of an individual’s attitude towards action, subjective norm related to a behavior (i. e., who approves or disapproves of the behavior), and the perceived control of the behavior (Giles, McClenahan, Cairns, & Mallet, 2004). This combination of an individual’s attitude, subjective nonns, and perceived behavioral control are infonned and driven by behavioral, nonnative, and control beliefs, which ultimately produce one’s intention to change behavior (Ajzen, 1991). This relationship is illustrated below in Figure 6.1.
FIGURE 6.1 Depiction of the key mechanisms and processes influencing behavior change within the Theory of Planned Behavior.
An individual’s behavioral beliefs (i.e., a favorable or unfavorable attitude towards a behavior) serve as the connection between one’s behavior to the specific outcome that the behavior is anticipated to produce or bring about. For example, when high school students believe that adopting environmentally friendly behaviors is likely to produce more positive outcomes, their attitudes towards these behaviors are likely to be more favorable (De Leeuw, Valois, Ajzen, & Schmidt, 2015). Although an individual may hold numerous behavioral beliefs regarding a specific behavior, only a relatively small number are easily accessible at any given moment. More specifically, when an individual considers the potential outcomes that will be produced from a behavior, an individual’s beliefs towards this behavior are most likely to be based on salient factors such as personal experiences, information sources, and inferences (Ajzen, 1991). Thus, an individual’s easily accessible beliefs—in conjunction with the subjective values of the anticipated outcomes—govern and determine the predominant attitudes towards the behavior.
Normative beliefs extend beyond the individual by involving one’s perceived behavioral expectations of key referent people or groups (e.g., one’s significant other, family, friends). The TPB assumes that nonnative beliefs, when combined with an individual’s motivation to comply with the different referents, directly inform and produce one’s subjective norms (i.e., the perceived social pressure to engage or not engage in a particular behavior). Moreover, an individual’s motivation to comply with these referents contributes to the subjective norm based on the direct proportion to an individual’s subjective probability that each referent perceives the individual should engage in the behavior of interest. For example, a high school student considering higher education is more likely to attend college if the student was raised by caregivers that valued education and if the student holds high regard for the opinions of the student’s caregivers.
Control beliefs involve an individual’s perceived presence of factors that may foster or hinder engagement in performance of a particular behavior. For example, an individual who is attempting to quit smoking may be influenced by factors such as the company smoking policy at their workplace. If this individual’s workplace did not have a specific policy regarding smoking, this will likely be perceived as a weak control factor. However, if the individual’s workplace does not permit smoking on company premises and includes sanctions for violations of said policy, this will likely be perceived as a strong control factor. Control beliefs can be perceived individually and may differentiate based on the perceived power of each control factor. From this combination of perceived control beliefs and the perceived power of each, an individual’s perceived behavioral control is determined. Specifically, an individual’s decision to engage in a particular behavior is weighed based on the perceived power of each control factor to impede or promote the behavior in direct proportion to the individual’s subjective probability that the control factor is readily available (Ajzen, 1991).