Theory of Reasoned Action and Theory of Planned Behavior
Theory of Reasoned Action
A foundational theory in understanding health behavior.
Theory of Planned Behavior
Extension of the Theory of Reasoned Action.
Concept – Theory Essence Sentence
Health behavior results from intention.
People are more likely to do something if they plan or aim to do it, than if they don’t.
Constructs
Several constructs influence intention:
Attitudes toward the behavior
Subjective/social norms
Volitional and behavioral control
Attitudes
Definition: A series of beliefs gives rise to an attitude.
Formula: Belief + Belief + Belief = Attitude
Example: Attitude toward vegetarianism where:
Better for the environment
No harm to animals
Healthier for my body
Resulting in: Positive Attitude → Likely to be vegetarian
Subjective Norms
Definition: Subjective norm is the perceived social pressure to engage or not to engage in a certain behavior.
These norms result from normative beliefs - beliefs about what significant others want us to do.
Important People Influencing Norms
Categories of significant others include:
Significant others
Parents
Children
Religious leaders
Friends
Health care providers
Faculty/teachers
Questions on Subjective Norms
How would subjective norms explain why teenagers begin smoking?
How would subjective norms explain why adults quit smoking?
Volitional Control
Definition: A behavior under volitional control is one that the individual can decide to engage in, at will.
Examples include:
Brushing your teeth
Skipping dessert
Exercising
Using sunscreen
Behavioral Control
Some behaviors are not under our willful (volitional) control.
The Theory of Reasoned Action is less effective in these situations due to this limitation.
Behavioral Control construct added; leads to the Theory of Planned Behavior.
Understanding Behavioral Control
Definition: Behavioral Control is one’s perceived control over the performance of a behavior.
Important to differentiate from self-efficacy, which refers to one's perceived ability to perform a behavior.
Control over performance is influenced by personal control beliefs - beliefs that may facilitate or hinder behavior performance.
Examples of Behavior Not Under Volitional Control
Situations illustrating lack of volitional control include:
Getting 8 hours of sleep (e.g., noisy roommates)
Avoiding secondhand smoke (e.g., family members smoking in the house)
Eating low sodium foods (e.g., family dynamics in shopping and cooking)
Visual Representation
Figure 3.3 Theory of Reasoned Action/Planned Behavior
Components include:
Volitional/Behavioral Control
Subjective Norms
Intention
Behavior
Attitudes
Reference: Modified from Rah, J. H., Hasler, C. M., Painter, J. E., & Chapman-Novakoski, K. M. (2004). Applying the theory of planned behavior to women's behavioral attitudes on and consumption of soy products. Journal of Nutrition Education, 36(5), 238-244.