L7 Research Methods?1: Background & Types of Research in?Clinical Psychology?

參考文獻/圖片來源：Pomerantz, A. (2013). Clinical psychology: science, practice, and culture (3rd ed.). Thousand Oaks, CA: SAGE Publications.

7.1 Background on Research Methods

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Example:?Conflict Between Parents & Children

? Some degree of conflict between?caregivers and children is typical.?Extreme forms are associated?increased risk for mental health?problems.

? Why do some parent-child?relationships have particularly high?degrees of conflict? What kinds of?problems do we see in these?relationships? How can we reduce?this conflict?

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- What factors influence conflict?

? Potential factors that might influence parent-child conflict: stress levels, parenting techniques, child behavior, parent mental health, child mental health, communication, child maltreatment, sources of support, etc.

? Research helps us figure out how all these variables relate?to one another, which helps us figure out how to address?the problem.

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- Specifying Hypotheses

? Expect links among: Harsh Parenting, Stress, and?Parent-Child Conflict

? Path diagrams: Schematics depicting relationships:

-?Double-headed arrow connecting two variables: Correlation

-?Single-headed arrow connecting two variables: Causation

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? Common variable relationships described in hypotheses:

- Correlational: Variables related in non-causal fashion: “Harsh Parenting, Stress, and Parent-Child Conflict are related”

- Causal: One variable (or more) causes another variable (or more): “Harsh Parenting and Stress both cause Parent-Child Conflict”

- Mediation: One variable accounts for?/ explains the?relationship between the others: “Harsh Parenting mediates link between Stress and Parent-Child Conflict”

? Stress leads to Parent-Child Conflict because it causes Harsh Parenting Techniques.

? Relationship between Stress and Parent-Child Conflict disappears if Harsh Parenting is added to model

- Moderation: A variable influences the strength or direction of the relationship between the others: “Stress moderates link between Harsh Parenting and Parent-Child Conflict”

? Strength of relationship between Harsh Parenting and Parent-Child Conflict varies based on how much Stress is present

? Stress increases likelihood of Parent-Child Conflict only if Harsh Parenting is already present

Independent & Dependent Variables

? Independent Variables - Manipulated by the experimenter

? Dependent Variables - Hypothesized to change as a result of the changes in the independent variables

Internal & External Validity

? Internal Validity of Study - Extent to which changes in the dependent variable can be attributed to changes in the independent variable

? External Validity of Study - Generalizability of findings beyond this specific study.?Same finding to be expected for different situations

High in internal validity - usually low in external validity

High in external validity - usually low in internal validity

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7.2 Research Designs

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? Correlational Studies, |r|<1

- Correlations have both magnitude and direction

? Magnitude is stronger as |r| increases

? Direction of association is positive or negative

- Positive r: as X increases, Y increases

- Negative r: as X increases, Y decreases

- Zero: independent variables

- Cannot be sure about causality

? “Third” variables may explain observed relationships

? Causal arrows may go in different directions (chicken & egg)

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? Experimental Studies

- Examine effect of experimentally manipulated independent variable (IV) on dependent variable (DV) across multiple persons

- Random assignment to levels of the IV

- Example: “Does manipulating level of alcohol consumption (IV) influence performance in a driving simulator (DV)?”

- Higher internal validity than correlational studies

- External validity varies across studies?(actually driving vs driving simulator)

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Between vs Within?Approaches:

? Between-Group: Evaluates groups at single time and the comparisons are made between the groups

? Within-Group: Follows same individuals over time and individuals are compared to themselves - May be very brief (i.e., before and after a task in a lab) or longer

? Mixed-Group: Includes features of both between and within-groups design

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? Quasi-Experimental Studies

- Used when researchers cannot randomly assign people to a particular group (either for practical or ethical reasons)

- Example: “Do children who experience emotional abuse (IV) differ in their ability to recognize facial emotions (DV) than children who have no abuse histories?”

- Lower internal validity than experimental studies

- Higher internal validity than correlational studies

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Time Frames?(all designs)

? Cross-Sectional: Evaluates sample(s) at single time

- Much cheaper, less time-intensive, good starting point

? Longitudinal: Follows same persons over time

- Helps understand development, course, and treatment of psychopathology

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? Meta-Analysis

- Integrates findings from multiple studies

- Refers to both a method and a statistical technique

- Example: Taylor, Swerdfeger, & Elsick (2014) performed a metaanalysis on studies related to vaccines and Autism Spectrum Disorder (ASD); included over 1.25 million children across many studies; found no connection between vaccines and ASD risk.

- Benefits of meta-analysis

? Greatly enhanced external validity.

? Greatly enhanced ability to detect small effects, that may be missed in a single study.

? Gold-standard approach to literature review and synthesis.

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Samples Used Across Designs

Types of Samples

- Community Sample

? Individuals from the community

? Usually relatively low rates of disorders

- Clinical Sample

? Individuals have the disorder?(e.g., have alcohol use disorder)

- Analogue Sample

? Individuals whose behavior?approximates, related to the disorder?of interest (i.e., heavy/binge drinkers?- have alcohol use disorder)

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7.3 Functions of Research in?Clinical & Counseling Psychology

Epidemiology

- Cornerstone of public health

- Identifies factors affecting the?health of populations

- Demonstrates the need for?prevention/intervention

- Helps determine funding priorities

? Epidemiology research in Clinical Psychology:

- Identify rates of mental disorders

- Identify rates of risk factors

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Epidemiology Studies in Clinical Psychology

? The National Comorbidity Survey Replication?- NCS-R (Kessler et al., 2004)

? Goal?- Uncover trends in mental health?disorder prevalence, impairment,?and service use; Get more detailed information?than previous studies

? Sample?- Nationally representative?US sample (N = 9,836)

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? Method: Face-to-face interviews (lasting ~2.5 hours, ranging from 1.5 to 6 hrs)

- Better accuracy than internet, phone, mail surveys and?higher quality data

- Higher response rates?(many people agree to participate)

- Ability to manage participant burden/fatigue (e.g.,?providing rests)

- Payment: $50

? Primary NCS-R Findings

- Comorbidity: 45% of people with 1 mental disorder had ≥ 2?diagnoses

- About 33% received “minimally adequate treatment” in the past?year

“minimally adequate treatment”?- number of sections received