HEALTH BELIEF
MODEL AND
THEORY OF
REASONED ACTION
Glanz, et al.
Origins of the Health Belief Model
(HBM)
◦ Developed in 1950’s by social
psychologists (Hochbaum, 1958)
◦ Derived from stimulus response theory
and cognitive theory
◦ Value-expectancy concepts evolve (i.e.
value avoiding illness/expect a specific
action will prevent illness)
Description of HBM Constructs
◦ Perceived Susceptibility- likelihood one will get disease or
condition
◦ Perceived severity- beliefs about gravity of contracting
disease/illness
◦ Perceived benefits-perceived benefits about available
actions to reduce threat
◦ Perceived barriers- belief about the “costs” of advised
health action
◦ Cues to action-strategies to activate readiness
◦ Self efficacy- confidence in one’s ability to take action
Measurement of HBM constructs
◦ Construct definitions need to be consistent w, HBM
theory conceptualized
◦ Measures need to be specific to behavior being
addressed and relevant to population
◦ Measure full range of factors that may influence
behavior for content validity
◦ Multiple items for each scale reduces measurement error
◦ Validity and reliability measures need to be reexamined
with each study
Apply the HBM constructs to the following health
issues:
◦ Mammogram screening in Latina women age 40
and older
◦ Prostate cancer screening for African American men
40 and over
◦ Osteoporosis in the GW (young women
only)freshman class
Limitations of HBM
◦ Individual and Linear model that assumes a
rational thought process
◦ HBM does not consider the emotional
component of behavior
◦ Cues to action are missing from the research
◦ Relationship between severity and susceptibility
is unclear (which comes first?) to determine
behavioral predictors
Theory of Reasoned Action (TRA)/ Theory of
Planned Behavior (TPB)
◦ Ajzen and Fisbein (1975) focused on constructs concerned w, individual
motivations/likelihood of performing certain behaviors
◦ TRA asserts the MOST important determinant of behavior is BEHAVIORAL
INTENTION
◦ TRA focuses on cognitive factors (beliefs/values) that determine motivation
(behavioral intention)
◦ Direct determinants of individuals behavioral intention is ATTITUDE toward
behavior and SUBJECTIVE NORMS associated with behavior
◦ TPB adds Perceived behavioral control over behaviors taking into account
situations where one may not have complete volition over behavior
◦ Postulates that perceived behavioral control is independent
of behavioral intention (person’s ease/difficulty with
performing behavior will affect behavioral intention)
◦ The most important determinant of behavior of IBM is Intention to perform
behavior; this is typically measured in the literature
◦Apply the constructs of TPB to
the following:
◦Healthy eating
◦Condom use
◦Smoking
Integrated Behavioral Model
◦ Constructs include:
◦ Intention or decision to perform the behavior
◦ Attitude, Experiential Attitude, Instrumental
Attitude
◦ Perceived norm, Injunctive norm, Descriptive
norm
◦ Personal agency, Perceived control, Selfefficacy
Construct
Definition
Behavioral Intention
Perceived likelihood of performing behavior
ATTITUDE
Experiential attitude (DM)
Overall affective evaluation of the behavior
ATTITUDE
Behavioral belief(ID)
Belief behavior performance is associated with
positive/negative things
ATTITUDE
Instrumental attitude (DM)
Overall evaluation of behavior
ATTITUDE
Evaluation
Value attached to behavioral outcome
ATTITUDE
Subjective Norm (DM)
Do most people approve/disapprove of
behavior?
PERCEIVED NORM
Normative belief (IM)
Belief about whether each person
agrees/disagrees
PERCEIVED NORM
Motivation to comply
Motivation to do what each person thinks
PERCEIVED NORM
Descriptive norm (DM)
Belief about if most people perform behavior
PERCEIVED NORM
Perceived Behavioral Control (DM)
Overall measure of perceived control over
behavior
PERSONAL AGENCY
Control belief (IM)
Perceived likelihood of occurrence of each
facilitating or constraining condition
PESONAL AGENCY
Perceived power
Perceived effect of each condition in making
behavioral performance difficult or easy
PERSONAL AGENCY
Self efficacy (DM)
Overall measure of ability to perform behavior
PERSONAL AGENCY
Self-efficacy belief (IM)
Perceived ability to overcome each constraining
PERSONAL AGENCY
Four types of elicitation
questions for TRA/TPB/IBM
◦ Positive or negative feelings about
performing behavior
◦ Positive or negative attributes or outcomes of
performing the behavior
◦ Individuals who they may listen to
oppose/favor behavior
◦ Situational or environmental facilitators and
barriers make behavior easy or difficult to
perform
Limitations of TRA/TPB/IBM
◦ It does not consider the role of environmental and
structural issues
◦ The linear nature of the theoretical constructs
◦ It assumes the person has acquired the opportunities and
resources to be successful in performing the desired
behavior, regardless of the intention
◦ The time frame between "intent" and "behavioral action" is
not addressed by the theory