Chapter 4 Reading Notes PSYCH338

Chapter Four: Research Methods

Goals of Research

• The primary goals of research in relation to psychopathology include understanding, explaining, and predicting mental disorders.

Research Methods in Psychopathology

1. Case Studies: These provide in-depth insights into individual cases of mental disorders, using qualitative data to help understand complex phenomena. However, they are limited in generalizability.

2. Correlational Research: This method examines relationships between variables without manipulating them. While it identifies patterns, it does not ascertain cause and effect.

3. Experimental Research: This approach involves manipulating variables to establish cause-and-effect relationships. It provides more reliable data regarding the impacts of different treatments or interventions.

Research Designs in Psychopathology

• Cross-Sectional Research: This design compares different age groups at a single point in time, useful for identifying prevalence and trends.

• Longitudinal Research: This strategy follows the same individuals over time, providing richer data on how disorders develop or ameliorate. It avoids cohort effects, which can skew findings in cross-sectional studies.

Ethical Considerations in Psychological Research

• Researchers must ensure ethical standards by obtaining informed consent from participants, maintaining confidentiality, and ensuring no harm comes to participants during or after the research. Ethical review boards play a crucial role in oversight.

Research Basics

• Hypothesis: An educated prediction that guides the research.

• Research Design: A structured plan for how to investigate the hypothesis through experimentation.

• Dependent Variable (DV): The outcome measured in the study, expected to change in response to the independent variable.

• Independent Variable (IV): The variable manipulated by the researcher to observe its effect on the DV.

• Validity: Internal validity measures the accuracy of the study results attributed to the IV, while external validity assesses the generalizability of results beyond the study sample.

• Testability: A hypothesis must be testable to be scientifically useful, allowing it to be confirmed or refuted via experimentation.

Correlation and Causation

• Correlation: Indicates the degree to which two variables are related. It can be positive or negative but does not imply causation.

  • Positive Correlation: Both variables increase or decrease together.

  • Negative Correlation: One variable increases while the other decreases.

• Directionality: This concerns whether variable A causes changes in variable B, or vice versa.

Epidemiology in Psychopathology

• This method focuses on understanding the prevalence and distribution of disorders within populations. It helps identify at-risk groups and the impact of mental health on society. Studies may reveal trends associated with age and mental health issues, such as sleep disorders.

Experimental Methods

• Randomized Clinical Trials: These are rigorous studies that allow researchers to determine the causal effects of an intervention through manipulation and control conditions.

• Control Groups: Necessary for comparison, control groups experience everything except the manipulation of the IV.

• Placebo Control Groups: Help assess the psychological effect of believing one is receiving treatment.

Single-Case Experimental Designs

• This design allows for the manipulation of variables on an individual basis, supporting cause-and-effect conclusions despite limited generalizability.

Measurement Techniques

• Repeated Measurement: Refers to observing behavior multiple times, offering insights into variability and trends over time.

• Withdrawal Design: Removing treatment to observe changes demonstrates treatment efficacy.

• Multiple Baseline Designs: Involves measuring behavior across settings or multiple behaviors to assess the impact of interventions.

Phenotypes and Genotypes

• Phenotypes: Observable characteristics influenced by genetic and environmental factors.

• Genotypes: The specific genetic makeup of an individual.

• Endophenotypes: These refer to genetic mechanisms that connect symptoms to underlying vulnerabilities in psychological disorders.

Research Strategies: Longitudinal and Cross-Sectional

• Cross-Sectional Design: Quickly compares different ages or groups to identify differences in values and experiences across cohorts.

• Longitudinal Design: Focuses on individual changes over time, avoiding cohort effects and enabling deeper understanding of development.

• Cross-Generational Effects: This refers to the limitations in generalizing longitudinal findings due to cultural and experiential differences across generations.

• Sequential Design: This combines aspects of both longitudinal and cross-sectional designs, allowing examination of multiple cohorts over time.

Informed Consent

• An essential ethical consideration wherein subjects agree to participate after being fully informed about the study's nature and their role within it.