1. Chapter 4 Research Methods in Clinical Psychology
Introduction to Clinical Psychology 2e hunsley & lee
PREPARED BY DR. cathy chovaz, king’s college, Uwo

2. Ways of Generating Research Hypotheses
Everyday Experience and Observation
Professional Experience and Observation
Addressing Applied Problems and Needs
Previous Research
Theory

3. Topics Relationship Between Variables Ethics in Research
Important Concepts to Clinical Research
Clinical Research Designs
Selecting the Participants
Selecting the Measures
Psychometric Properties of the Measures

4. Relationships Between Variables
Correlation – the variables are associated in some way
Moderation – one variable influences the direction or size of another
Mediation - one variable explains the relationship between two others

5. Ethics in Research (some principles)
Institutional approval
Informed consent
Inducements for participation
Deception in research
Debriefing
Humane care for animals
Reporting results

6. Important Concepts to Clinical Research
Internal validity – controlling for biases
External validity – how representative and applicable the study is
Statistical conclusion validity – whether the study was designed in a way to adequately test hypotheses through statistical methods

7. Clinical Research Designs
1. Case Study – detailed description of a case, which can allow for a great deal of hypothesis generating
Down side: many threats to internal validity making it difficult to generalize
2. Single case designs A-B (two measures of symptoms pre- and post-treatment
A-B (designs with a number of clients)
A-B-A (designs with one person at different time points)

8. Clinical Research Designs
3. Correlational designs – association among variables (most commonly used design)
Does not imply causality
‘Median splits’ on a particular variable - dichotomizing
Factor analysis – the underlying structure of a variable
Mediator vs. Moderator designs
Structural equation modeling

9. Clinical Research Designs
4. Quasi-experimental designs - comparing groups when random assignment is not available or ethical
5. Experimental Designs (the ‘gold standard’ in clinical research) – random assignment and experimental manipulation
Randomized controlled trials (RCT)

10. Clinical Research Designs
6. Meta-analysis – summarizing several similar studies through a statistical analysis
Effect size – a statistical measure of how strong the experimental effect is (i.e., statistical significance does not say how strong the effect is, only that it is unlikely to have randomly occurred)

11. Selecting the Participants
Importance of selecting a representative sample (age, gender, SES, ethnicity, etc.)
Sampling strategy – how participants are chosen/recruited
Probability sampling – requesting participants from say, every 10th person in a neighborhood
Non-probability sampling – recruiting through a method that will reach as many people as possible

12. Selecting the Participants
Setting the sample size – making sure there are enough participants to detect differences in groups
Low power
Sufficient sample size
Statistical significance
Clinical significance

13. Selecting the Measures
Self-Report Measures – participant report
Informant-Report Measures – report by someone who knows the participant
Rater Evaluations – research assistant rates the participant
Performance Measures – how a participant does on a task (e.g., reaction time or behavioural measure)

14. Selecting the Measures
Projective Measures – participant responses to ambiguous stimuli, which may reflect the internal state of the participant
Observation of Behaviour - coding systems used to summarize complicated behaviour
Psychophysiological Measures – a range of measures reflecting biological markers (e.g., heart rate, blood pressure, neural activity)
Archival Data – Data stored for some other purpose used for research (e.g., police records, health care utilization records, and academic records)

15. Psychometric Properties of the Measures
Reliability:
Internal Consistency: Homogeneity of test items
Test-Retest Reliability: Stability of scores on a measure over time
Inter-Rater Reliability: The consistency of scores on a measure across different raters or observers.

16. Psychometric Properties of the Measures
Validity:
Content Validity: How fully and accurately the measure represents the construct being assessed
Face Validity: How much the measure overtly appears to be measuring the construct of interest.
Criterion Validity: The association of a measure with a related criterion
Concurrent Validity: The association of a measure with other relevant data measured at the same point in time.

17. Psychometric Properties of the Measures
Validity (cont.):
Predictive Validity: The association of a measure with other relevant data measured at some future point in time.
Convergent Validity: The association between a measure and either other measures of the same construct or conceptually related constructs
Discriminant Validity: The association between measures that, conceptually, should not be related
Incremental Validity: The extent to which a measure adds to the prediction of a criterion beyond what can be predicted with other measurement data

18. Copyright
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