Chapter 3 lecture PPT

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3
Research
Eric J. Mash
A. 2016
Wolfe
©David
Cengage Learning
© Cengage Learning 2016
A Scientific Approach
• Requires that a claim be based on
theories backed up by empirical evidence
from well-designed studies before
conclusions are drawn
• Is especially important in abnormal child
psychology
– A simple connection between cause and
effect may be obscured by complex
interactions and a combination of variables
© Cengage Learning 2016
A Scientific Approach (cont’d.)
• Reasons for skepticism about research in
abnormal child psychology
– Experts frequently disagree
– Studies appearing in mainstream media are
oversimplified
– Findings often conflict with one another
– Research has led to different treatments—
some have been helpful; some have had no
effect; and some have been harmful
© Cengage Learning 2016
When Science is Ignored
• Ineffective practices not based on
scientific evidence may be used with
potentially damaging effects
• Pseudoscience demonstrates benefits
through anecdotes or testimonials
• The difference between science and
pseudoscience is:
– The quality of the evidence, how it was
obtained, and how it is presented
© Cengage Learning 2016
The Research Process
• Research in abnormal child psychology is
a multistage process:
1. Developing a hypothesis on the basis of
observation, theory, and previous findings
2. Identifying the sample to be studied,
selecting measurement methods, and
developing research design and procedures
3. Gathering and analyzing the data and
interpreting the results
© Cengage Learning 2016
The Research Process (cont’d.)
© Cengage Learning 2016
Nature and Distribution of Childhood
Disorders
• Epidemiological research is the study of
incidence, prevalence, and co-occurrence
of disorders
– Incidence rates: the extent to which new
cases of a disorder appear over a specified
time period
– Prevalence rates: all cases (new and existing)
observed during a specified time period
© Cengage Learning 2016
Correlates, Risks, and Causes
• Correlates: variables associated at a
particular point in time
– No clear proof that one precedes the other
• Risk factors: variables that precede an
outcome of interest
– Increase the chance of a negative outcome
• Protective factors: variables that precede
an outcome of interest
– Decrease the chance of a negative outcome
© Cengage Learning 2016
Moderating and Mediating Variables
• Moderating variables influence the
direction or strength of the relationship of
variables of interest
– Have an independent effect on the existing
relationship between two variables
• Mediating variables impact the process,
mechanism, or means through which a
variable produces a particular outcome
– Account for some or all of the apparent
relationship between two variables
© Cengage Learning 2016
Example of a Moderator Variable
© Cengage Learning 2016
Mediating Variables
© Cengage Learning 2016
Interventions
• Randomized controlled trials (RCTs)
– Children are randomly assigned to different
treatment and control conditions
• Treatment efficacy
– Whether a treatment can produce changes
under well-controlled (research) conditions
• Treatment effectiveness
– Whether the treatment can be shown to work
in clinical practice
© Cengage Learning 2016
Methods of Studying Behavior
• Standardization
– A process that specifies a set of standards or
norms for a method of measurement
• Reliability: the consistency or repeatability
of results
– Internal consistency: measurement method
remains the same
– Interrater reliability: agreement of observers
– Test-retest reliability: results between tests
are stable over time
© Cengage Learning 2016
Methods of Studying Behavior (cont’d.)
• Validity
– Face validity: the extent to which a measure
appears to assess the construct of interest
– Construct validity: whether scores on a
measure behave as predicted
– Convergent validity: reflects the correlation
between related measures
– Discriminant validity: the degree of correlation
between unrelated measures
© Cengage Learning 2016
Validity (cont’d.)
• Criterion-related validity: how well a
measure predicts behavior in specific
settings
– At the same time (concurrent validity)
– In the future (predictive validity)
© Cengage Learning 2016
Value of Methods and Measurement
© Cengage Learning 2016
Measurement Methods
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Interviews
Questionnaires
Checklists and rating scales
Psychophysiological recordings
Brain imaging
Performance measures
© Cengage Learning 2016
Measurement Methods (cont’d.)
• Direct observations of behavior
• Intellectual, academic, and
neuropsychological tests
© Cengage Learning 2016
Interview, Questionnaire, and Observation
© Cengage Learning 2016
Reporting Methods
• Assess perceptions, thoughts, behaviors,
feelings, and past experiences of the child,
parents, and teachers
– Includes unstructured clinical interviews,
highly structured diagnostic interviews, and
questionnaires
– A self-report measure provides information
about one’s own behavior, feelings, and
thoughts
© Cengage Learning 2016
Reporting Methods (cont’d.)
• Informant-report measure - someone who
knows the child well provides information
based on observation
– Inaccuracies may occur - failure to recall
events, selective recall or bias, etc.
– Requires verbal ability - not reliable with
young children
– Must be sensitive to the language and cultural
background of person being evaluated
© Cengage Learning 2016
Psychophysiological Methods
• Assess the relationship between
physiological processes and behavior
– Autonomic nervous system activity
• Examples: heart rate, blood pressure, respiration,
pupil dilation, and electrical skin conductance
– Limitations
• Inconsistent findings; inference often involved; and
susceptibility to extraneous influences
– Electroencephalogram (EEG) measures the
brain’s electrical activity
© Cengage Learning 2016
Neuroimaging Methods
• Structural brain imaging procedures study
brain anatomy
– Magnetic resonance imaging (MRI) - radio
signals produce fine-grained analyses of brain
structures
– Coaxial tomography (CT) scan reveals
various brain structures
© Cengage Learning 2016
Neuroimaging Methods (cont’d.)
• Functional brain imaging procedures study
brain functioning
– Functional magnetic resonance imaging
(fMRI) registers neural activity in functioning
areas of the brain
– Positron emission tomography (PET) scans
assess cerebral glucose metabolism
– Diffusion MRI produces images showing
connections between brain regions
© Cengage Learning 2016
Observational Methods
• Benefits of structured observations
– Are cost-effective
– Allow for focused attention
– Are useful for studying infrequent behavior
– Allow for greater control over the situation
• Limitation of structured observations
– Uncertainty of whether the observations are a
representative sample of behavior
© Cengage Learning 2016
Research Strategies
• Internal validity
– The extent to which a particular variable,
rather than extraneous influences, accounts
for the findings
• External validity
– The degree to which findings can be
generalized to other people, settings, times,
measures, and characteristics
© Cengage Learning 2016
Research Strategies (cont’d.)
• Identifying the sample
– A careful definition of the sample is critical
– Comorbidity: the simultaneous occurrence of
two or more disorders
– Random selection is rare in child
psychopathology studies
– Child studies often use samples of
convenience
© Cengage Learning 2016
General Research Strategies
• Nonexperimental and experimental
research
– One goal is to simplify and isolate variables to
study them more closely
– Characteristics of true experiments
• Researchers have maximum control over the
independent variable
• Subjects are randomly assigned
• Needed control conditions are applied
• Possible bias sources are controlled
© Cengage Learning 2016
Nonexperimental and Experimental
Research (cont’d.)
• Correlational studies examine
relationships among variables
– Causality cannot be determined
• Random assignment of participants to
treatment conditions:
– Helps control for participant characteristics
• Natural experiments involve comparisons
between conditions that already exist
© Cengage Learning 2016
Prospective and Retrospective Research
• Retrospective designs
– Sample is identified at the current time and
asked for information relating to an earlier
time
– Data are highly susceptible to bias and
distortion in recall
© Cengage Learning 2016
Prospective and Retrospective Research
(cont’d.)
• Real-time prospective designs
– Sample is identified and followed over time
• Data is collected at specified time intervals
– Problems related to bias and distortion in
recall are minimized
– These designs are time consuming and
susceptible to sample attrition
© Cengage Learning 2016
Analogue Research
• Evaluates a specific variable under
conditions that approximate the situation
for which one wishes to generalize
• Focus is on a circumscribed research
question under well-controlled conditions
• It is difficult to know if similar effects would
occur in real-life circumstances
© Cengage Learning 2016
Research Designs
• Case Study
– Involves an intensive, anecdotal, observation
and analysis of an individual child
– Rich source of descriptive information
– Viewed as unscientific and flawed
• Characterized by uncontrolled methods and
selective biases; by inherent difficulties integrating
observations and drawing valid inferences; and by
generalizations from one child to other children
© Cengage Learning 2016
Research Designs (cont’d.)
• Single-Case Experimental Designs
– Applicable in evaluating the impact of a
clinical treatment
– Involves systematic repeated assessment of
behavior over time
• The subject serves as own control
– Limitations
• Possible interactions between treatment and
subject characteristics; limited generalization of
findings; and subjectivity in evaluating the data
© Cengage Learning 2016
A-B-A-B (reversal) design
© Cengage Learning 2016
Multiple-Baseline Design Across Situations
© Cengage Learning 2016
Research Designs (cont’d.)
• Between-group comparison designs
compare experimental and control groups
• Cross-sectional/longitudinal studies look at
change over time
– Cross-sectional: individuals at different ages
or periods of development are studied at the
same point in time
– Longitudinal: individuals are studied over time
at different ages or periods of development
© Cengage Learning 2016
Research Designs (cont’d.)
• Qualitative Research
– Focuses on narrative accounts, description,
interpretation, context, and meaning
– Purpose is to describe, interpret, and
understand the phenomenon of interest
• In the context in which it is experienced
– May be biased by researcher’s values and
preferences
– Findings cannot be generalized to other
individuals
© Cengage Learning 2016
Ethical and Pragmatic Issues
• Informed consent
– Before agreeing to participate, all participants
must be fully informed of the nature of the
research, including:
• Risks, benefits, expected outcomes, alternatives,
and option to withdraw from the study at any time
– Minor’s consent must be obtained from
parents or legal guardian
© Cengage Learning 2016
Ethical and Pragmatic Issues (cont’d.)
• Assent
– The child agrees to participate
– Must be obtained if a child is around age 7 or
older
© Cengage Learning 2016
Ethical and Pragmatic Issues (cont’d.)
• Voluntary Participation
– Participation in research must be voluntary
– Researcher must balance successful
recruiting with not placing pressure on
potential participants
© Cengage Learning 2016
Ethical and Pragmatic Issues (cont’d.)
• Confidentiality and anonymity
– Disclosed information must be kept
confidential
– Individuals must be advised about any
exceptions
– Disclosures of abuse are a common problem
in child research
• Nonharmful procedures
– Should not cause physical or psychological
harm
© Cengage Learning 2016
Ethical and Pragmatic Issues (cont’d.)
• Other ethical and pragmatic concerns
– Ethical concerns
– Longitudinal research - may involve
unexpected crises, unforeseen consequences
of research, and issues about continuing the
research that affect a child’s well-being
© Cengage Learning 2016
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