Title: Health Psychology
1Health Psychology
- Lecture 2
- Theory and Research
2Lecture 2 - Outline
- Part 1
- Theory and Research
- Part 2
- Placebo Effects
- Part 3
- Assignment 1
3Theory
- Example Heart disease is due to excess levels of
cholesterol - Provide a framework for simplifying and
describing data in a meaningful way - A set of related assumptions from which, by
logical deductive reasoning, testable hypotheses
can be drawn - Theories are judged in terms of their usefulness
- Clearly stated?
- Bring together known facts?
- Enable us to make predictions?
4Theories are useful!
- Shelly Taylor (1990). American Psychologist, 45,
40-50. - As a field, health psychology has made
substantial contributions to the understanding of
healthy behaviors and to the comprehension of the
myriad factors that undermine health and often
lead to illness. -
- Much of the strongest work has involved
providing theoretical and conceptual frameworks
that elucidate the (non)practice of health
behaviors, the role of stress in affecting
illness and illness behavior these theoretical
conceptualizations constitute major contributions
inasmuch as they are often lacking in traditional
medicine and medical practice. -
- For example, it is difficult for physicians to
understand why 93 of patients fail to adhere to
certain aspects of their treatment regimens
social psychological models not only make sense
of these data but suggest ways of ameliorating
them.
5Health Belief Model
- Cognitive-behavioral model (cognitive influence
on behav.) - Readiness to seek preventative health care is
shaped by 4 core beliefs - Perception of SUSCEPTIBILITY to disease
- (perceived personal vulnerability)
- Perceived SEVERITY of disease
- Perceived BENEFITS of action
- Perceived COSTS of action
(Rosenstock, 1966)
6Health Belief Model
- Readiness to Take Action Perceived Threat
- Readiness to Change Behavior Perceived Benefit
of Taking Action (Threat Reduction) - Cost-Benefit Analysis
Perceived Threat
Perceived Benefit
Likelihood of Acting
7Health Belief Model - Evaluation
- No place for emotions (fear, denial)
- Assumes people make rational choices
- Best predictor of actual behavior barriers to
health practices - Overall shows moderate predictive power
- Works moderately well for dental visits, safe
sex, etc
Perceived Threat
Perceived Benefit
Likelihood of Acting
Cues to Action (internal/external)
8Health Belief Model
9Theory of Reasoned Action
- Azjen and Fishbein (1980)
- Cognitive-behavioral model (cognitive influence
on behav.) - Behavioral INTENTION is the best predictor of
behavior (!)
Attitudes
Subjective Norms
INTENTION
BEHAVIOR
10Theory of Planned Behavior
- Azjen (1985)
- Cognitive-behavioral model (cognitive influence
on behav.) - Behavioral INTENTION is the best predictor of
behavior (!)
Attitudes
Subjective Norms
INTENTION
Behavioral Control
BEHAVIOR
11Theory of Planned Behavior
12Summary - Cognitive Approaches
- Cognitive approaches are good at predicting
behavior requiring conscious decisions (e.g.,
going to dentist), but not good when when
behavior becomes habitual (e.g., substance
abuse).
13Learning Theory Approaches
- Focus on situations and rewards, not cognitions
- Health behavior habits controlled by cues
- not necessarily under conscious control
- Broad-spectrum or multimodal approaches
Reward (R)
BEHAVIOR (B)
Situation (SD)
14Research in Health Psychology
- the ideal health psychologist is a competent
and highly trained individual equipped to
intervene at both the individual and community
levels, and who is able to conduct high quality
research - (Richards, 1992)
15Research
- Body of scientific evidence
- Largely free of self-serving bias
- evolutionary rather than revolutionary
- typically takes time and develops gradually
- Research in response to theory (tentative
explanation)
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17Research in Health Psychology
- Health involves many variables - hard to
research - Numerous misleading claims (e.g., carcinogenic
personality ) - But research does not have to be perfect to be
useful! - Types of research design
- Experiment
- Ex post facto design (quasi experimental)
- Single-subject
- Correlational
- Retrospective
- Prospective (longitudinal)
- Epidemiology
18Experiment (controlled clinical trial)
- Manipulate independent variable and measure
dependent variable - Able to determine causality
- Characteristics of a good experiment
- .
- .
- .
- .
- .
-
19Quasi -Experiment (ex post facto)
- Not always able to manipulate the independent
variable - Ethical and practical reasons
- Not able to determine causality
- Groups self-select (no random assignment or
manipulation) - Observe dependent variable
- Able to identify risk factors
20Correlational Designs
- Observe two (or more) variables
- Data analysis
- Simple correlations (2 variables),
- Path analysis/structural equation modeling
(multiple variables) - Not able to determine causality
- Able to identify risk factors
- Correlational studies are often misunderstood
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22Prospective Studies
- Begin with whole population and observe over time
- Initially healthy
- Cross lagged correlations
- Problems
- Expensive
- Time consuming
- Attrition rates
23Epidemiology
- Scientific discipline that considers the various
factors determining the frequency, distribution,
and cause of a disease or disorder - Risk Factor any characteristic or condition
which occurs with greater frequency in people
with a disease than people without. - Morbidity disease
- Incidence number of new cases in a specified
time interval - Prevalence total of cases in a specified time
interval - Mortality death
- of deaths to a known cause
- (premature death death before age 75)
24Treatments and Interventions
3 elements of a treatment/intervention 1) Assump
tions / Goals (Theory!) 2) Techniques
(Theory-driven) 3) Treatment Evaluation a)
Outcome - is the person better? b) Process -
why is the person better?
253) Treatment Evaluation
- Experiment (controlled clinical trial)
- Manipulate independent variable and measure
dependent variable - Able to determine causality
- Characteristics of a good experiment
- Random sampling
- Random assignment
- Valid manipulation of independent variable
- Valid and reliable measurement of dependent
variable - Control extraneous variables
- Placebo effect
26Placebo
Active treatment substance or procedure that is
explicitly directed at the symptoms of the
condition in question. Placebo substance or
procedure that does not specifically target the
condition being treated
27Placebo Effect
- Provide about 35 of improvement for a variety of
conditions. - Physical conditions - headaches, warts, etc
- Psychological conditions - pain, depression, etc
- Example - Depression
- Cognitive-Behaviour.... 65-70
- Antidepressant medication. 65
- Placebo drug 30
28Why the placebo affects
- Expectancies
- Anticipation of the emotional and physiological
response - Non-Specific Factors
- Features, or incidental elements, common to all
therapeutic interventions - Eg - doctor-patient relationship, hope,
suggestion, expectancies - Demand Characteristics
- Classical Conditioning
29Can a placebo have a negative effect?
30Can a placebo have a negative effect?
- Nocebo effect - the flipside of the placebo
effect - case study shes a TC!
- Inert pills can produce negative side effects
- experiment reactions to a poisonous plant
31Placebo effect
- limitations of the placebo effect
- ethical considerations
- implications for research
32Implications for Research
- Double-blind trials (Sarafino, p. 26)
- Diagnosis
- Intervention Independent variable
-
- Assess on relevant dependent variables
- Follow-up (long-term gains)
Experimental group (active drug)
Placebo group (inert drug)
Control group (no pills)
33Implications for Research
- Results if the drug is effective!
-
Illness
Experimental group (active drug)
Placebo group (inert drug)
Control group (no pills)
34Tutorial Assignment 1
- Practice exercise
- Effect of herbal extracts on health
35Empirical Evidence
- Hoodia Weight-Loss Pill
- A few years ago South African scientists
discovered the plant contained a previously
unknown molecule, which has since been christened
P 57. - You can find pills containing Hoodia extract
advertised on the Internet. - Would you give this pill to patients who want to
lose weight? - Educated doctors need to know
- .
- .
36Practice Exercise - Modern Juice
- add a supplement to boost your health!
- Vitamin C (with potent antiviral and
antibacterial properties, vitamin C plays a vital
role in strengthening the immune system,
especially with regard to preventing and treating
the common cold) - Echinacea (organic herbal extract, mobilizes the
immune system response to bacterial invaders by
increasing the production of white blood cells) - Royal Jelly (the sole food of the queen bee, this
premium quality extract is a super-nutrient and
well-known booster of immune function and is rich
in protein, vitamins, and enzymes) - Organic Wheatgrass (nutritional scientists have
hailed it as the most powerful blood, tissue, and
colon cleanser. As it detoxifies the liver and
kidneys, it enriches the blood with an array of
vitamins and minerals. 1 or 2 oz a day helps
maintain a strong immune system)
37Practice Exercise - Modern Juice
- add a supplement to boost your health!
- Hawaiian Spirulina (an organic blue green
micro-algae which contains high doses of 10
readily assimilated essential nutrients.
Beneficial for stress-related mental and physical
fatigue and iron deficiency) - Panax Chinese Ginseng (considered the most
stimulating of all ginsengs. Helpful to relieve
stress and fatigue, and to improve mental and
physical performance, stamina, and exercise) - Kava Kava (a sacred plant extract from the pepper
plant, native to the South Sea islands. Promotes
a deep restful sleep, pain relief with sedative
effects and muscle relaxation) - Ginko Biloba (an anti-oxidant rich herb that has
a scavenging effect on free-radicals. It
increases dopamine, which aids in memory and
mental alertness)
38Practice Exercise - Modern Juice
- We are interested in whether the consumption of
juice supplements is related to improved health
and greater resistance to illness. - Boost immune system
- vitamin C, echinacea, royal jelly, wheatgrass
- Relieve stress
- Hawiian Spirulina, Ginseng, Kava, Ginko Biloba
- Design a correlational study to test this. What
can you conclude? - Design a true experiment. What can you
conclude?
What will you measure, how will you measure it?
(reliability and validity)
39Design a Correlational Study/True Experiment
- Hypothesis/Rationale
- Participants
- Measures
- Predictor variable
- Outcome variable
- Mechanism
- Procedure/Design
- Data analysis
- Conclusions
40Term Paper 1
- We are interested in whether higher levels of
physical activity are associated with lower
cholesterol levels. - Design an ex-post facto (quasi-experimental)
study to test this. What can you conclude? - Design a true experiment. What can you
conclude? - Maximum Length 1000 words
- Due date Monday, October 4
- References Sarafino (pp. 25-32, 241-242)