CHAPTER 4 RESEARCH METHODS (PP )

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1 1 Research 2 Methods Return CHAPTER 4 RESEARCH METHODS (PP ) Research Studies Hypothesis Ind/Dep Variable Int/Ext Validity Concepts Significance Statistical Case Study Corr Coeff Average Client Clinical Incidence Correlation Epidem. Research Designs Prevalence Experiment Control Group Prevention Genes Families Placebo Adoption Single-Case Process Time & Culture Repeated Measures Cross Sectional Longitudinal Twins Double-Blind Multiple Baseline Withdrawal SCIENCE AND ABNORMAL BEHAVIOUR(P. 105) Nature of Science Way of knowing world unlike normal everyday ways of knowing Latter susceptible to various biases Science values Empiricism, Objectivity, and Replication Science demands rigorous standards of proof (Evidence!) Science is ways to test Hypotheses and Theoretical claims Science is human enterprise, hence value laden, not value free Data Points Theories 3 SCIENCE AND ABNORMAL BEHAVIOUR (P. 105) Questions Driving a Science of Psychopathology What problems cause distress or impair functioning? Why do people behave in unusual ways? How can we help people behave in more adaptive ways? Basic Components of Research (pp ) Start with Hypothesis or Educated Guess Must be testable: not all hypotheses testable Research Design Method to test hypotheses Independent variable (IV): causes or influences behaviour Dependent variable: behaviour influenced by IV 4 CONSIDERATIONS IN RESEARCH DESIGN (PP ) Balancing internal vs. external validity Internal validity: Confidence that effects are due to the independent variable External validity: Extent to which the findings are generalizable Increase internal validity by minimizing confounds Use of control groups Use of random assignment procedures Use of analogue models (University of Alberta researchers Pierce and Epling(1994) have developed an animal model of anorexia nervosa) Relation between internal and external validity 5 STATISTICAL METHODS AND CLINICAL MEANINGFULNESS (PP ) Statistical Methods Branch of mathematics Helps to protect against biases in evaluating data Statistical vs. Clinical Significance Statistical significance: results not due to chance or coincidence Clinical significance: whether results are clinically meaningful Statistical significance does not imply clinical meaningfulness Need to balance Statistical and Clinical Significance Effect size: d = (M1 M2)/SD, r, Social Validity Generalizability and Patient Uniformity Myth 6 1

RESEARCH DESIGNS 7 Case Study Correlational (Non-experimental) Designs Experimental Designs Single Case Studies CASE STUDY METHOD (PP.

- Generate testable hypotheses Limitations of Case Study Internal validity weak: Often entails numerous confounds, and lacks scientific rigor and suitable controls 8 MULTIPLE PERSONALITY (OSGOOD

2 RESEARCH DESIGNS 7 Case Study Correlational (Non-experimental) Designs Experimental Designs Single Case Studies CASE STUDY METHOD (PP ) Nature of Case Study Extensive observation and detailed description of client May include interviews, diaries, letters, tests, treatment accounts Foundation of early historic developments in psychopathology e.g., Osgood & multiple personality: Three Faces of Eve (+1) Especially useful to: - Describe unusual phenomena, methods (interview, assessment, treatments) - Disconfirm universally known information - Generate testable hypotheses Limitations of Case Study Internal validity weak: Often entails numerous confounds, and lacks scientific rigor and suitable controls 8 MULTIPLE PERSONALITY (OSGOOD SEMDIFF) 9 CORRELATIONAL RESEARCH (PP ) Correlational (Non-experimental) Studies Statistical relation between two or more variables No independent variable is manipulated Nature of Correlation and Strength of Association Range from 1.0 to +1.0, with 0 indicating no relationship (+1, +2, +3) Negative vs. positive relation indicated by sign of correlation Size of r indicates strength: +.5 stronger than -.3 (r 2 =.25 vs..09) Epidemiological Research Study incidence, prevalence, and course of disorders and disease e.g., AIDS, extent of trauma following a disaster Correlation and Causality Correlation does not imply causation AND 0 Correlation does not imply NO causation Problem of directionality: X Y, Y X, Z X,Y; e.g., TV violence NEUROTICISM& BECK DEPRESSION SCALE 12 r = +1.0 r = -1.0 r = 0 r = +? C4:12 2

ANXIETY AND DAILY HASSLES 13 C4:14 C4:13 15 ILLUSORY CORRELATION Perceive relationship where NONE exists (r = 0) Viken et al (2005) Perceived association between Happiness and Body Type Method 186

Questionnaire Results Reported negative association between Weight and Happiness in stimuli, even though true r = 0 Bias stronger for participants with higher levels of eating disorder symptoms

111-113) Nature of Experimental Research Manipulation of independent variables Attempt to establish causal relations Premium on internal validity Group Experimental Designs Nature and purpose of

3 ANXIETY AND DAILY HASSLES 13 C4:14 C4:13 15 ILLUSORY CORRELATION Perceive relationship where NONE exists (r = 0) Viken et al (2005) Perceived association between Happiness and Body Type Method 186 undergraduate women rated pictures of women on Happiness, Degree Overweight, and Attractiveness Later judged covariationbetween attributes and completed Eating Disorder Examination-Self-Report Questionnaire Results Reported negative association between Weight and Happiness in stimuli, even though true r = 0 Bias stronger for participants with higher levels of eating disorder symptoms Conclusion Possible cognitive bias may help maintain and enhance concerns about shape and weight RESEARCH BY EXPERIMENT (PP ) Nature of Experimental Research Manipulation of independent variables Attempt to establish causal relations Premium on internal validity Group Experimental Designs Nature and purpose of control groups: Placebo vs. double-blind controls Comparative Treatment Designs Type of group design Compare different forms of treatment in similar persons Used to address treatment process and treatment outcome EXPERIMENTAL DESIGNS SINGLE-CASE EXPERIMENTAL DESIGNS (PP ) Nature of Single-Subject Design Rigorous study of single cases over varied experimental conditions and time Repeated measurement and evaluation of variability, level, and trend Emphasizes internal validity Type of Single-Subject Design Withdrawal Design: Nature, assets, and liabilities Multiple Baseline Design: Assets and liabilities 18 3

19 C4:20 WITHDRAWAL DESIGN SINGLE-CASE EXPERIMENTAL DESIGNS (P. 114) Figure 4.

interaction between genes, experience, and behaviour Phenotype vs.

Allow separation of environmental from genetic contributions Twin studies: Psychopathology in fraternal vs.

116-119) 22 STUDYING BEHAVIOUR OVER TIME (PP. 119-121) 23 24 Rationale and Overview How does problem or behaviour change over time?

4 19 C4:20 WITHDRAWAL DESIGN SINGLE-CASE EXPERIMENTAL DESIGNS (P. 114) Figure 4.2 Evaluation of trend and variability in Wendy s anxiety via the singlesubject design MULTIPLE BASELINE DESIGN 21 Behavioural Genetics Examine interaction between genes, experience, and behaviour Phenotype vs. genotype Strategies Used in Genetic Research Family studies: Examine behavioural pattern/emotional traits in family members Adoptee studies: Allow separation of environmental from genetic contributions Twin studies: Psychopathology in fraternal vs. identical twins Genetic linkage and association studies: Locate site of defective gene STUDYING GENETICS (PP ) 22 STUDYING BEHAVIOUR OVER TIME (PP ) Rationale and Overview How does problem or behaviour change over time? Important in prevention and treatment research Time-Based Research Strategies Cross-sectional design: Problem of cohort effect (+1) Longitudinal design: Problem of cross-generational effect (+1) Sequential design: Combine cross sectional and generational designs Assets and Liabilities of Time-Based Research Strategies STUDYING BEHAVIOUR OVER TIME (P. 120) 4

5 Reasoning ability score 60 ADULTHOOD- COGNITIVE CHANGES Cross-sectional method suggests decline Longitudinal method suggests more stability Age in years 25 Cross-Sectional Study Compare people of different ages with one another Dashed line in graph Longitudinal Study Same people restudied and retested over long period Solid line in graph STUDYING BEHAVIOUR ACROSS CULTURES (PP ) Value of cross-cultural research Overcome ethnocentric research Determine universality of findings Pros and Cons of cross cultural research Assets: Clarify how psychopathology manifests in different ethnic groups Liabilities: many challenges Equivalence: language and testing, response biases, 26 THE POWER OF A RESEARCH PROGRAM (PP ) Components Set of inter-related research questions: A tree with many branches Draw on diverse methodologies in finding answers Conducted in stages, often involving replication Research Ethics: Institutional Review Boards, APA Codes Informed consent: Historical evolution post WWII Competence: Ability to provide consent Voluntarism: Lack of coercion Full information: Necessary information for informed decision Comprehension: Understand benefits and risks of participation 27 SUMMARY OF RESEARCH METHODS 28 Nature of Research: Establish and test hypotheses Value of research designs depends on questions posed Abnormal psychology is founded on Scientific method Understand nature of abnormality and human suffering Understand complex causes of psychological disorders Biological, including Genetics AND Environmental, including Psychological Understand course of psychological disorders Understand how to prevent (e.g., spanking) and treat (e.g., Cognitive-Behavioural) psychological disorders Importance of Research Program and Replication Research must occur in context of ethical considerations and values 5

Design of Experiments & Introduction to Research

Design of Experiments & Introduction to Research 1 Design of Experiments Introduction to Research Definition and Purpose Scientific Method Research Project Paradigm Structure of a Research Project Types