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Research Methods and Abnormal Psychology
Chapter 3
Basic Components of Research Study (cont.)
Internal vs. External Validity Internal validity – Confidence that effects are due to
the independent variable External validity – Extent to which the findings are
generalizable
Ways to Increase Internal Validity by Minimizing Confounds Use of control groups or statistical control Use of random assignment procedures Use of analog models
Relation Between Internal and External Validity
Types of Research Designs
Descriptive designs Involves measurement of independent variables, but
not manipulation by experimenter Answers questions about relations among variables Does not allow us to infer causation Examples: case studies and epidemiology
Experimental designs Involves manipulation of an independent variable to
observe the effect Allows stronger inference about causation Examples: analog studies and randomized trials
Descriptive Designs: Case Studies
Nature of the Case Study Extensive observation and detailed description of a
client Foundation of early historic developments in
psychopathology
Limitations of the Case Study Lacks scientific rigor and suitable controls Often entails numerous confounds Useful for generating scientific hypotheses, but not
testing
Descriptive Designs: Epidemiology
Study incidence, prevalence, and course of disorders and disease Uses “correlational method”
The Nature of Correlation Statistical expression of covariation between two
variables No independent variable is manipulated
Nature of Correlation and Strength of Association Range from –1.0 to 0 to +1.0 Positive vs. negative correlation
Correlation and Its Relation to Causation Problem of directionality “Third variable” problem Correlation does not imply causation
Experimental Designs: Analog Studies
Experimenter manipulates independent variable to create phenomena analagous to psychological disorder Animal models – depression, aggression May be used to test treatment mechanisms or
effects of psychological disorders Advantage: larger potential samples Disadvantage: limited external validity to clinical
samples
Experimental Designs: Randomized Trials
True experiment Participants randomly assigned to experimental or
control group Independent variable is present in experimental
group, absent in control group Example: treatment outcome studies
Other considerations Placebo can control for participant expectancy
effects Double-blind design can control for experimenter
expectancies
Studying Change over Time
How does the problem or behavior change over time? Important in prevention and treatment research
Cross-sectional designs Assess different groups of age cohorts at one time Advantage: faster Disadvantage: cohort effects limit inference of
causes Logitudinal designs
Follow one group over time, across different ages Advantage: better inference about causes Disadvantage: cross-generation effects limit
generalizability
Ethics in Research
Sources of Ethical Guidelines Institutional Review Boards APA Ethics Codes Federal Regulations
Considerations Informed consent – Historical evolution post WWII Competence – Ability to provide consent Voluntarism – Lack of coercion Full information – Necessary information to make an
informed decision Comprehension – Understanding about benefits and
risks of participation
Anxiety Disorders
Chapter 4
Nature of Anxiety and Fear
Anxiety Future-oriented mood state characterized by marked
negative affect Somatic symptoms of tension Apprehension about future danger or misfortune
Fear Present-oriented mood state, marked negative affect Immediate fight or flight response to danger or threat Strong avoidance/escapist tendencies Involves abrupt activation of the sympathetic
nervous system
Anxiety and Fear are Normal Emotional States
From Normal to Disordered Anxiety and Fear
Characteristics of Anxiety Disorders Psychological disorders – Pervasive and persistent
symptoms of anxiety and fear Involve excessive avoidance and escapist tendencies Symptoms and avoidance causes clinically significant
distress and impairment
The Anxiety Disorders: An Overview
Generalized Anxiety Disorder Panic Disorder with and without Agoraphobia Specific Phobias Social Phobia Posttraumatic Stress Disorder Obsessive-Compulsive Disorder
Generalized Anxiety Disorder:The “Basic” Anxiety Disorder
Overview and Defining Features Excessive uncontrollable anxious apprehension and
worry about life events Coupled with strong, persistent anxiety Somatic symptoms differ from panic (e.g., muscle
tension, fatigue, irritability) Persists for 6 months or more
Facts and Statistics 4% point prevalence Females outnumber males approximately 2:1 Onset is often insidious, beginning in early adulthood Tendency to be anxious runs in families
Panic Disorder with and without Agoraphobia
Overview and Defining Features Experience of unexpected panic attack (i.e., a false
alarm) Develop anxiety, worry, or fear about having another
attack or its implications Agoraphobia – Fear or avoidance of situations/events
associated with panic Symptoms and concern about another attack
persists for 1 month or more Facts and Statistics
3.5% point prevalence Two thirds with panic disorder are female Onset is often acute, beginning between 25 and 29
years of age
The Phenomenology of Panic Attacks
What Is a Panic Attack? Abrupt experience of intense fear or discomfort Accompanied by several physical symptoms (e.g.,
breathlessness, chest pain)
DSM-IV Subtypes of Panic Attacks Situationally bound (cued) panic – Expected and
bound to some situations Unexpected (uncued) panic – Unexpected “out of the
blue” without warning Situationally predisposed panic – May or may not
occur in some situations
Panic Is Analogous to Fear as an Alarm Response
Panic Disorder with and without Agoraphobia
Overview and Defining Features Experience of unexpected panic attacks (i.e., a false alarm) Develop anxiety, worry, or fear about having another
attack or its implications Agoraphobia – Fear or avoidance of situations/events
associated with panic Symptoms and concern about another attack persists for 1
month or more Facts and Statistics
3.5% point prevalence Two thirds with panic disorder are female Onset is often acute, beginning between 25 and 29 years
of age
Overview and Defining Features Extreme and irrational fear of a specific object or
situation Markedly interferes with one's ability to function Recognize fears are unreasonable, but go to great
lengths to avoid phobic objects
Facts and Statistics About 11% point prevalence for one or more specific
phobias Females are again over-represented Phobias run a chronic course, with onset beginning
between 15 and 20 years of age
Specific Phobias: An Overview
Social Phobia: An Overview
Overview and Defining Features Extreme and irrational fear/shyness in social and
performance situations Markedly interferes with one's ability to function Often avoid social situations or endure them with
great distress Generalized subtype – Social phobia across
numerous social situations
Facts and Statistics About 13% lifetime prevalence Females are slightly more represented than males Onset is usually during adolescence with a peak age
of onset at about 15 years
Posttraumatic Stress Disorder (PTSD): An Overview
Overview and Defining Features Requires exposure to an event resulting in extreme
fear, helplessness, or horror Person continues to re-experience the event (e.g.,
memories, nightmares, flashbacks) Avoidance of cues that remind person of event Emotional numbing and interpersonal problems are
common Markedly interferes with one's ability to function PTSD diagnosis cannot be made earlier than 1 month
post-trauma
Facts and Statistics About 7.8% point prevalence Combat and sexual assault are the most common
traumas
Overview and Defining Features Obsessions – Intrusive and nonsensical thoughts,
images, or urges that one tries to resist or eliminate Compulsions – Thoughts or actions to suppress the
thoughts and provide relief Most persons with OCD display multiple obsessions Most persons with OCD present with cleaning and
washing or checking rituals
Obsessive-Compulsive Disorder (OCD): An Overview
Facts and Statistics About 2.6% lifetime prevalence Most persons with OCD are female OCD tends to be chronic Onset is typically in early adolescence or young
adulthood
Obsessive-Compulsive Disorder (OCD):Causes and Associated Features