Health Psychology – Renner (Lecture 3)
Social-cognitive Factors in Health Behavior Change
Misjudging Risk Information
first step in changing health behavior is to become aware of the connections between
behavior and health → most intervention programs provide information about health risks
and hazards to improve knowledge about causes of health and illness
simply making information about risks available does not necessarily allow people to make
informed judgments and decisions because information can be easily misinterpreted
risk communication: increasing knowledge about the nature, magnitude, and significance of
health risks → underlying assumption that people can only make appropriate decision about
preventive actions when perceive risk accurately
factual risk or objective risk defined by technical experts as annual injury, fatality rate etc
(e.g. diseases represent greater factual risk than accidents → lay person thinks opposite)
◦ studies show judgmental biases in processing of risk information → laypersons and
health providers do not calculate risk in the same “rational” manner as technical experts
to determine the magnitude of risk
◦ Instead of multiplying the chance of infection by the chance of dying (e.g. for HIV and
Hepatitis B), which results in an overall risk of 1 percent for both diseases, people
focused their judgments on the lethal consequences, while ignoring the probability of
infection (fear HIV more than Hepatitis B) → fear of certainty of death
▪ risk of other contagious diseases might be underestimated, since death is not
perceived as a certain outcome once one has become infected, which might result in
a failure to take necessary precautions
▪ more efficient treatments will encourage risk behavior
risk perception has two aspects: perceived severity of a health condition (the amount of harm
that could occur), and personal vulnerability (subjective probability that once could fall
victim to that condition) toward it → relationship of both described by a simple probability
by severity interaction (“normative” or “rational” principle)
◦ personal vulnerability or likelihood of the event is zero, the resulting perceived risk
should also be zero, regardless of how serious the event may be
◦ interest in obtaining protection is not always a function of severity and likelihood →
type of the relationship among severity, likelihood, and motivation to act varied with the
severity and likelihood of the hazard
people make finer distinctions at the low end of the likelihood scale than at the high end →
confronted with hazard with a 50 percent chance of occurring (high cholesterol) may display
the same reaction as individuals who are confronted with a hazard with an 80 percent chance
of occurring (smoking)
→ risk communication must supply information about the relative risks of acquiring one
disease versus another to help people anchor the likelihood of occurrence and severity in
appropriate ways
Many risks have a relatively low probability for any single exposure, however, small
probabilities add up over repeated exposures to create a substantial overall risk (e.g.
smoking) → Misjudging the cumulative risk of increasing exposure to risks could jeopardize
appropriate behaviors and in the worst case encourage extensive risk behaviors
long-term effectiveness of precautions could be misconstrued (e.g. when taking birth control
the risk for pregnancy is 0.98 of 100 women for one year, therefore, 2 women would get
pregnant, however, after 10 years 20% of the same group will become pregnant, although
they still perceive risk as 2%) → individuals need to understand how the risk of conception
accumulates over repeated exposure, and to what degree this could be reduced through the
use of contraceptive methods
, Health Psychology – Renner (Lecture 3)
◦ most laypersons do not realize that contraceptive effectiveness declines over time, thus,
a short-term perspective on effectiveness may promote unrealistically optimistic
estimations about long-term outcomes, since individuals are not aware how rapidly small
risks add up → short-term and long-term contraceptive effectiveness information should
be provided (complete risk information)
health risk becomes even more complex when multiple risks are considered (e.g. smoking
and drinking)
◦ study participants believed that engaging in only one risk behavior (heavy alcohol
consumption or heavy smoking) results in the same risk as engaging in both at the same
time → two risks considered as disjunctive instead of synergisic
→ hazards should include information about potential synergistic or additional effects,
as otherwise people might seriously misconstrue their overall risk
Underestimating Self-relevant Risk
general perceptions of risk (e.g., “Smoking is dangerous”) and personal perceptions of risk
(e.g., “I am at risk because I am a smoker”) often differ to a great extent
◦ especially when comparing with others, one’s view of the risk is somewhat distorted →
tend to see themselves less likely than others to experience health problems in future:
unrealistic optimism or optimistic bias
◦ additionally, individuals prone to illusion of safety in a risky world
▪ e.g. even smokers who demonstrated a smoking behavior that they themselves
judged as highly risky nonetheless viewed their own personal risk as only average
→ important barrier for convincing people to change health habits because bias may
function to dissuade them from engaging in protective health actions
people acknowledge a higher risk with increasing age and declining health, but that aging
did not curb unrealistic comparative risk perceptions (still thought peers more at risk)
→ to reduce unrealistic optimism is to provide additional information about the risk faced by an
average peer (e.g. when think about risk-reducing factors a typical peer might list results in lower
unrealistic optimism → unrealistic optimism caused because not think carefully about person
comparing to)
→ to reduce ambiguity (since recipients have to infer the magnitude of their personal
risk) people should be informed of existence of health risk in personalized manner to enhance self-
relevance and should image themselves as possible victims → assess individuals’ risk status by
either self-administered questionnaires or biomedical measures
individuals process and respond to feedback about their personal health risk in a self-
defensive manner
◦ however, unfavorable medical feedback causes prominent denial only when recipients
believed that they had no possibility of reducing the threat by modifying their behavior
Forming an Intention to Change: Continuum Models of Health Behavior
continuum models → way in which predictors (e.g. social norms, personal vulnerability)
combine to influence actions is expected to be the same for everyone
◦ e.g. Theory of Reasoned Action, Theory of Planned Behavior, Protection Motivation
Theory
▪ beside risk perception two other variables are considered to play a major role in
theories: (a) outcome expectancies, and (b) perceived self-efficacy
(a) Outcome Expectancies
not only need to be aware of a health threat, also need enough knowledge about how to
regulate their behavior → understand link between action and outcomes
Social-cognitive Factors in Health Behavior Change
Misjudging Risk Information
first step in changing health behavior is to become aware of the connections between
behavior and health → most intervention programs provide information about health risks
and hazards to improve knowledge about causes of health and illness
simply making information about risks available does not necessarily allow people to make
informed judgments and decisions because information can be easily misinterpreted
risk communication: increasing knowledge about the nature, magnitude, and significance of
health risks → underlying assumption that people can only make appropriate decision about
preventive actions when perceive risk accurately
factual risk or objective risk defined by technical experts as annual injury, fatality rate etc
(e.g. diseases represent greater factual risk than accidents → lay person thinks opposite)
◦ studies show judgmental biases in processing of risk information → laypersons and
health providers do not calculate risk in the same “rational” manner as technical experts
to determine the magnitude of risk
◦ Instead of multiplying the chance of infection by the chance of dying (e.g. for HIV and
Hepatitis B), which results in an overall risk of 1 percent for both diseases, people
focused their judgments on the lethal consequences, while ignoring the probability of
infection (fear HIV more than Hepatitis B) → fear of certainty of death
▪ risk of other contagious diseases might be underestimated, since death is not
perceived as a certain outcome once one has become infected, which might result in
a failure to take necessary precautions
▪ more efficient treatments will encourage risk behavior
risk perception has two aspects: perceived severity of a health condition (the amount of harm
that could occur), and personal vulnerability (subjective probability that once could fall
victim to that condition) toward it → relationship of both described by a simple probability
by severity interaction (“normative” or “rational” principle)
◦ personal vulnerability or likelihood of the event is zero, the resulting perceived risk
should also be zero, regardless of how serious the event may be
◦ interest in obtaining protection is not always a function of severity and likelihood →
type of the relationship among severity, likelihood, and motivation to act varied with the
severity and likelihood of the hazard
people make finer distinctions at the low end of the likelihood scale than at the high end →
confronted with hazard with a 50 percent chance of occurring (high cholesterol) may display
the same reaction as individuals who are confronted with a hazard with an 80 percent chance
of occurring (smoking)
→ risk communication must supply information about the relative risks of acquiring one
disease versus another to help people anchor the likelihood of occurrence and severity in
appropriate ways
Many risks have a relatively low probability for any single exposure, however, small
probabilities add up over repeated exposures to create a substantial overall risk (e.g.
smoking) → Misjudging the cumulative risk of increasing exposure to risks could jeopardize
appropriate behaviors and in the worst case encourage extensive risk behaviors
long-term effectiveness of precautions could be misconstrued (e.g. when taking birth control
the risk for pregnancy is 0.98 of 100 women for one year, therefore, 2 women would get
pregnant, however, after 10 years 20% of the same group will become pregnant, although
they still perceive risk as 2%) → individuals need to understand how the risk of conception
accumulates over repeated exposure, and to what degree this could be reduced through the
use of contraceptive methods
, Health Psychology – Renner (Lecture 3)
◦ most laypersons do not realize that contraceptive effectiveness declines over time, thus,
a short-term perspective on effectiveness may promote unrealistically optimistic
estimations about long-term outcomes, since individuals are not aware how rapidly small
risks add up → short-term and long-term contraceptive effectiveness information should
be provided (complete risk information)
health risk becomes even more complex when multiple risks are considered (e.g. smoking
and drinking)
◦ study participants believed that engaging in only one risk behavior (heavy alcohol
consumption or heavy smoking) results in the same risk as engaging in both at the same
time → two risks considered as disjunctive instead of synergisic
→ hazards should include information about potential synergistic or additional effects,
as otherwise people might seriously misconstrue their overall risk
Underestimating Self-relevant Risk
general perceptions of risk (e.g., “Smoking is dangerous”) and personal perceptions of risk
(e.g., “I am at risk because I am a smoker”) often differ to a great extent
◦ especially when comparing with others, one’s view of the risk is somewhat distorted →
tend to see themselves less likely than others to experience health problems in future:
unrealistic optimism or optimistic bias
◦ additionally, individuals prone to illusion of safety in a risky world
▪ e.g. even smokers who demonstrated a smoking behavior that they themselves
judged as highly risky nonetheless viewed their own personal risk as only average
→ important barrier for convincing people to change health habits because bias may
function to dissuade them from engaging in protective health actions
people acknowledge a higher risk with increasing age and declining health, but that aging
did not curb unrealistic comparative risk perceptions (still thought peers more at risk)
→ to reduce unrealistic optimism is to provide additional information about the risk faced by an
average peer (e.g. when think about risk-reducing factors a typical peer might list results in lower
unrealistic optimism → unrealistic optimism caused because not think carefully about person
comparing to)
→ to reduce ambiguity (since recipients have to infer the magnitude of their personal
risk) people should be informed of existence of health risk in personalized manner to enhance self-
relevance and should image themselves as possible victims → assess individuals’ risk status by
either self-administered questionnaires or biomedical measures
individuals process and respond to feedback about their personal health risk in a self-
defensive manner
◦ however, unfavorable medical feedback causes prominent denial only when recipients
believed that they had no possibility of reducing the threat by modifying their behavior
Forming an Intention to Change: Continuum Models of Health Behavior
continuum models → way in which predictors (e.g. social norms, personal vulnerability)
combine to influence actions is expected to be the same for everyone
◦ e.g. Theory of Reasoned Action, Theory of Planned Behavior, Protection Motivation
Theory
▪ beside risk perception two other variables are considered to play a major role in
theories: (a) outcome expectancies, and (b) perceived self-efficacy
(a) Outcome Expectancies
not only need to be aware of a health threat, also need enough knowledge about how to
regulate their behavior → understand link between action and outcomes
