chapter 3 research methods used to study child behavior disorders
TRANSCRIPT
Chapter 3
Research Methods Used to Study Child Behavior Disorders
Science and Common Sense
• Science is an extension of common sense that emphasizes systematic questioning
Research Questions
• Descriptive Research Questions ask about the nature of a phenomenon
• Difference research questions ask if there is a difference between phenomena
• Relationship research questions (correlational questions) asks to what degree phenomena are related
Research Paradigms: Distinctions, Descriptions, and Illustrations
Methodology Distinctions
• Experimental and non-experimental methods are mirror images of one another in some ways– Experimental – investigator manipulates the
treatment given to a participant in an environment that is carefully controlled
– Non-experimental – investigators observe, analyze and describe phenomena as they exist
Quantitative and Qualitative Methods
• Quantitative – conducted in controlled a way that results can be reduced to numerical presentation
• Qualitative – emphasizes reluctance to intervene in naturally occurring phenomena
Quantitative vs Qualitative
• Quantitative – Usually occurs in more controlled environment,
so researcher can be more confident in ascribing results to treatment variable
– Controlled environment more artificial and can make participants differently than in their normal setting
Quantitative and Qualitative
• Qualitative– Usually occurs in more natural and less
controlled environment, which are less likely to influence participant behavior
– Relative absence of control can contribute to unreliable data
Quantitative Methods
• Characterized by manipulation of the treatment or condition under study – Factor manipulated is independent
(experimental) variable– Measure, means by which treatment effect is
determined is dependent variable
Quantitative: continued
• Preference for precise hypothesis state at outset
• Preference for precise definitions state at the outset
• Data reduced to numerical scores• Much attention to assessing and improving
reliability of scores obtained from instruments
Quantitative: continued
• Assessment of validity through variety of design procedures with reliance on statistical indices
• Preference for random techniques for obtaining meaningful samples
• Preference for precise descriptions of procedures
Quantitative: continued
• Preference for specific design control for procedural bias
• Preference for statistical summary of results
• Preference for breaking down of complex phenomena into specific parts for analysis
• Willingness to manipulate aspects, situations, or conditions
Qualitative Methods
• Nonexperimental involves observation, analysis and description of phenomena rather than manipulation of treatment variables
Qualitative: continued
• Observation – data collection strategy that can be used in several research methods– Vary in degree of involvement of researcher
• Participant observation – observer takes part in activities and environment being observed
• Nonparticipant observation – observer is not or is only minimally involved in observed setting
Qualitative: continued
• Case Studies – in-depth examination of the behavior of an individual or small social unit– Provide important depth, complexity and
quantity of information– Information may not be generalizable– Vulnerable to investigator bias
Qualitative: continued
• Preference for hypotheses that emerge as study develops Preference for definitions made in context or as study progresses
• Preference for narrative description• Preference for assuming that reliability of
inferences is adequate• Assessment of validity through cross-checking of
sources of information (triangulation)
Qualitative: continued
• Preference for expert information samples• Preference for narrative/literary descriptions
of procedures• Preference for logical analysis in controlling
or accounting for extraneous variables (describing what else seems to be going on)
• Primary reliance on researcher to detect and minimize procedural bias
Qualitative: continued
• Preference for narrative summary of results
• Preference for holistic description of complex phenomena (describing the whole picture)
• Unwillingness to tamper with naturally occurring phenomena
Quasi-Experimental Designs
• Investigations in which participants cannot be randomly assigned to groups– Participants history cannot be controlled
Studying Development
• Longitudinal design – selects a sample of participants for an extended period of time, repeating assessment intermittently
• Cross-sectional design – simultaneously samples different groups of participants at several age levels and compares dependent variables across the age groups
Longitudinal Designs: limitations
• Participants development may be altered by the repeated assessments – “test-wise”
• Participant attrition – participants move away, refuse to continue or die
• Measures originally used may become dated in very long studies
Cross-sectional Designs: limitations
• Different cohorts or groups are being compared
• Age range can be so great that sociocultural or historical changes have been substantial
Time-Series Designs
• Investigations in which an independent variable is manipulated across two or more phases and the dependent variable is monitored at each phase
• Used to assess the effect of treatment on the behavior of a small number of participants
• Clinicians can treat individuals while systematically colleting information
• Many measurements are collected over time
Time Series Designs: limitations
• Measurements are taken on small number of individuals (or even one) – Results may not be generalizable– Types of participants are frequently atypical
Group Experiments
• More participants are included than in time-series
• Small number of measurements
• Types of group designs– Repeated measures design (pretest and posttest
comparison)– Multifactor designs – include two or more
experimental variables
Meta-Analysis
• Facilitates the analysis and interpretation of multiple results from different studies
• Allows researchers to statistically analyze and synthesize the findings of many previous empirical studies – Uncover consensus– Can present integrated picture of overall results
Fundamentals of Research Design
• Control – eliminating the systematic influence of all variables except the one being studied– All factors must be equivalent for both groups
except the independent variable – Procedures must be equivalent for both groups
Common Design Mistakes
• Internal validity – technical soundness of an investigation in terms of control
• External validity – experiments generalizability, how well can results be applied to other participants, settings and treatments
Common Design Mistakes
• Placebo effects – changes in participants’ behavior or performance that occur simply because they are in an experiment and not because of a particular treatment or intervention
Avoiding Design Pitfalls
• Random Sampling – Researchers use a selection process in which
each individual in the population has an equal chance of being chosen to participate in a study
– It is assumed that since each person has an equal chance of selection, that the characteristics of the participant sample will represent those of the entire population
Avoiding Design Pitfalls
• Experimental Matching– Procedures by which a researcher forces group
equivalence in terms of characteristics thought to be important for the particular study being conducted
Ethical Issues in Conditioning Research
• Ethical issues critical because psychology involves people working with other people and controlling aspects of their lives
Protecting welfare of participants
• Harm can be physical or psychological stress, or social embarrassment
• Cannot completely eliminate stress of any kind for participants– Potential harm weighed against potential
benefits of research
Informed Consent
• Capacity – persons ability and legal authority to consent to participate in a research project – Children may not be old enough to give legal
consent or cannot give consent because of mental disorders
• Information – Investigators must provide complete, and clearly communicated information regarding the study– Participants with behavior disorders may have
difficulty understanding information no matter how well it is communicated
• Voluntariness – Participants must participate of their own free will without coercion– Participants may feel coercion simply because
the researcher may represent a power figure for them