1. Outline: Lecture 3 – Jan. 21/03 [Chapter 3 - Research]
The Scientific Approach
The Research Process
Common Research Topics
Forms of Measurement
Defining Research Terminology
General Approaches to Research
Research Designs
Research Methods
Qualitative Research
Ethical Issues

2. The Scientific Approach
Theory - propositions that explain phenomena.
Hypothesis – an educated guess; a tentative assumption
Purpose of Scientific Approach: to describe phenomena and offer explanations for them.
Reasons for skepticism of research:
experts will often disagree
research findings are often in conflict
research will sometimes lead to different recommendations
research conclusions are often qualified

3. The Research Process

4. Common Research Topics
1. Nature & Distribution of Childhood Disorders
2. Risks, Causes, and Correlates
3. Moderating and Mediating Variables
See Figure 3.3 in text
4. Outcomes associated with childhood problems
5. Interventions
Treatment efficacy
Treatment effectiveness
Epidemiological research: addresses questions about the nature and distribution of childhood disorders
Incidence rates: the extent to which new cases of a disorder appear over a specified time period
Prevalence rates: all cases, whether new or previously existing, that are observed during a specified time period
Risk factor: variable that precedes an outcome of interest and increases the chances that the outcome will occur
Protective factor: variable that precedes an outcome of interest and decreases the chances that the outcome will occur
Correlated variables: variables associated at a particular point in time with no clear proof that one precedes the other
Moderating variable: a factor that influences the direction or strength of the relationship between other variables of interest
Mediating variable: the process, mechanism, or means through which a variable produces a particular outcome; describes what happens at the psychological or neurobiological level to explain how one variable results from another
Interventions
Treatment efficacy: whether or not a treatment can produce changes under well-controlled conditions
Treatment effectiveness: whether the treatment can be shown to work in actual clinical practice, rather than in laboratory conditions

5. Forms of Measurement 1. Reporting
includes unstructured clinical interviews, highly structured interviews, and questionnaires
inaccuracies may occur because of inability to recall events, selective recall or bias, and intentional distortions
requires a certain level of verbal ability, therefore often not considered reliable with children under age 7 or 8

6. Forms of Measurement [cont’d]
2. Psychophysiology and Neuro-imaging
physiological responses recorded include: heart rate, blood pressure, respiration, pupil dilation, and electrical skin conductance
limitations of physiological measures include: inconsistency, high level of inference often involved, and susceptibility to extraneous influences
electroencephalogram (EEG) measures electrical activity of the brain
neuroimaging procedures examine the structure and/or function of the brain

7. Forms of Measurement [cont’d]
3. Observation
may range from unstructured, naturalistic observations to highly structured
compared to naturalistic observations, structured observations are often cost-effective, allow for focused attention, are useful for studying infrequent behavior, and allow for greater control over the situation
major limitation is that one cannot be certain the observations are a representative sample of behavior

8. Identifying the Sample
A careful definition of the sample is critical for comparability of findings across studies
Must consider comorbidities among the sample
Random selection is rare in child psychopathology studies; often need to use a sample of convenience

9. Defining the Variables of Interest
A variable must be defined so that it can:
1. Be measured consistently over time.
2. Be measured consistently across researchers.
3. Provide an accurate measure of the behaviour of interest.
Operational definition: a description of a construct in objective, measurable terms.

10. Research Terminology
Standardization: the process by which a set of norms is specified for a measurement procedure so that it can be used consistently across different assessments
Reliability: the consistency of a measure, either across raters or time
Types of reliability:
inter-rater agreement - having multiple raters rate the same item, and then comparing their data.
test-retest reliability - whether the same results can be achieved when a measure is used more than once.
internal consistency - how well the questions within a measure relate to each other.

11. Research Terminology
Validity: the extent to which the method actually measures the construct of interest
Types of validity:
face validity - the appearance of validity.
convergent validity - a relationship between two measures of the same topic.
discriminant validity - lack of a relationship between two measures of different topics.
criterion-related validity - predictive ability either in the present (concurrent validity) or in the future (predictive validity).

12. Validity Internal validity:
the extent to which change in the dependent variable is due to the manipulation of the independent variable.
may be threatened by maturation, effects of testing, subject selection biases
External validity:
the extent to which findings of a particular experiment can be generalized to other subjects under other circumstances.
may be threatened by subject reactivity to participation, the setting, and the time measurements are made

13. General Approaches to Research
Experimental vs Non-experimental Research
In true experiments, researchers have maximum control over the independent variable, subjects are randomly assigned, and possible sources of bias are controlled – can determine cause and effect
Correlation studies only examine relationships among variables- causality cannot be determined
Natural experiments involve comparisons between conditions that already exist

14. General Approaches to Research [cont’d]
Prospective vs Retrospective Research
Real-time prospective designs: sample is followed longitudinally over time [follow-forward method]; time consuming and susceptible to sample attrition Retrospective designs: sample is asked for information relating to an earlier time period [follow-back method]; highly susceptible to recall bias and distortion
Analogue Research
evaluation of a specific variable under conditions that only resemble the situation to which one wishes to generalize

15. Research Designs Between-Group Comparison Studies
involves comparisons between experimental and control groups
Cross-Sectional Studies
individuals at different ages or stages of development are studied at the same point in time
often efficient and less susceptible to attrition and practice effects
do not allow for inferences regarding change and are susceptible to cohort effects

16. Research Designs Longitudinal Studies
same individuals are studied over time
Strengths: can see how behaviour changes over time
helps eliminate 3rd variable factor
Weakness: attrition
expensive
sociocultural changes over time
are measures valid at all ages
subjects become test-wise
Accelerated Longitudinal Studies [Sequential] combination of longitudinal and cross-sectional approaches
support for developmental change over entire age range
control for societal change

17. Non-experimental Methods
Case Studies: intensive and usually anecdotal observations and analyses of an individual child
Strengths: rich in detail
aids intervention planning
Weakness: investigator bias [reliability issue]
not generalizable [validity issue]
2. Observational Studies: Naturalistic or Controlled
Strengths: good for generating hypotheses
Weakness: inter-rater reliability
observer bias
subject reactivity

18. Non-experimental Methods
3. Correlational Research - where the relationship or degree of association between variables is examined.
Correlation Coefficient (Pearson r) - describes the strength and direction of a relationship between two variables; ranges between -1 and +1.
Strengths: useful in generating hypotheses and when ethical considerations preclude manipulations
Weakness: cannot rule out third unknown variable
statistical vs clinical significance

19. Correlation - Examples

20. Experimental Methods 1. True Experimental Design
Random assignment to groups
independent variable [IV]
dependent variable [DV]
2. Quasi-experimental & Mixed
Existing groups [e.g. age]
manipulation of IV
Strengths: can determine cause & effect
Weakness: cannot be used when ethical considerations preclude manipulation
weak in external validity

21. 3. Single-Case Experimental Designs
often used to evaluate the impact of treatments
involves repeated assessment of behavior over time, replication of treatment effects within the same subject, and the subject serving as own control
common examples are the A-B-A-B (reversal) design and the multiple-baseline design
weaknesses include possible interactions between treatment and subject characteristics, limited generality of findings, and subjectivity and inconsistency of visual inspection of the data

22. Single Subject Designs A-B-A-B (reversal)

23. Single Subject Designs

24. Qualitative Research
Purpose is to describe, interpret, and understand the phenomenon of interest in the context in which it is experienced
Although intensive and intimate, may be biased by researcher’s values and preferences, and findings cannot be generalized to other individuals

25. Ethical Issues 1. Informed Consent and Assent
informed consent must be obtained from parents
child’s assent must be obtained when child is around age 7 or older
2. Voluntary Participation
participation in research must be voluntary
may be compromised by subtle pressure and coercion

26. Ethical Issues 3. Confidentiality and Anonymity
disclosed information must be kept confidential
individuals must be advised at the outset of any exceptions to confidentiality
disclosures of abuse common problem in child research
4. Non-harmful procedures
no research procedures may be used that may harm a child physically or psychologically