© cengage learning 2016 eric j. mash david a. wolfe research 3
TRANSCRIPT
© Cengage Learning 2016 © Cengage Learning 2016
Eric J. MashDavid A. Wolfe
Research
3
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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
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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
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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
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• 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
The Research Process
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The Research Process (cont’d.)
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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
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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
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• 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
Moderating and Mediating Variables
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Example of a Moderator Variable
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Mediating Variables
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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
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• 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
Methods of Studying Behavior
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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
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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)
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Value of Methods and Measurement
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• Interviews
• Questionnaires
• Checklists and rating scales
• Psychophysiological recordings
• Brain imaging
• Performance measures
Measurement Methods
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• Direct observations of behavior
• Intellectual, academic, and neuropsychological tests
Measurement Methods (cont’d.)
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Interview, Questionnaire, and Observation
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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
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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
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• 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
Psychophysiological Methods
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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A-B-A-B (reversal) design
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Multiple-Baseline Design Across Situations
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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
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• 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
Research Designs (cont’d.)
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• 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
Ethical and Pragmatic Issues
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• Assent – The child agrees to participate
– Must be obtained if a child is around age 7 or older
Ethical and Pragmatic Issues (cont’d.)
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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
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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
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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