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Research Methods: Design and Ethics. Impart Seminar January 16, 2006 Annette Browne, Lynda Dechief, Erin Dunn, Josie Geller. Participation Biological perspectives Gender based analysis: “What does gender have to do with addictions?”. Introduction and Objectives.
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Research Methods: Design and Ethics Impart Seminar January 16, 2006 Annette Browne, Lynda Dechief, Erin Dunn, Josie Geller
Participation • Biological perspectives • Gender based analysis: • “What does gender have to do with addictions?” Introduction and Objectives
Overview of qualitative and quantitative • methodologies • Article discussion • Generating research questions • Break • Approaches to study design Outline
Internal Validity External Validity Internal vs. External validity
Internal Validity Tightly controlled “laboratory” conditions Experimental control over variables of interest Random selection and assignment Low generalizability External Validity Application in a clinical or field setting Little or no experimental control Less stringent selection or assignment High generalizability Internal vs. External validity
Example: Readiness and motivation for change in the eating disorders
Internal Validity Does the treatment work under optimal conditions? Efficacy Study: Clinical trial of Readiness and Motivation Therapy (RMT) External Validity Does the treatment work under real world conditions? Effectiveness Study: Evaluation of RMT as implemented in primary care clinics Research Questions
Methodological Issues • Selection of participants • Assignment of study participants • Operational definitions • Measurement • Analyses • Conclusions
Selection of Participants • Convenience sampling • Random sampling
Selection of Participants • Convenience sampling • Individuals seen in the EDP at SPH • College student subject pool • Random sampling • All individuals with an ED in British Columbia
Assignment of Study Participants • Random assignment • Non random assignment
Assignment of Study Participants • Random assignment • Use of a random digit table/coin toss to assign participants to group • Non random assignment • CQI research – studying cohorts • Consecutive admissions to program
Operational Definitions Do we have an agreed upon definition of what we think we are measuring?
Operational Definitions Do we have an agreed upon definition of what we think we are measuring? • Concepts for which operational definitions are needed: • What is recovery? • What is abstinence? • What is resilience? • What is motivation? • What is quality of life?
Measurement • Properties of a good measure: • Test-retest reliability • Internal consistency • Concurrent validity • Discriminant validity • Criterion validity
Measurement • Properties of a good measure: • Test-retest reliability • Stability of the measure • Internal consistency • Consistency of items within a scale/measure • Concurrent validity • Relation to other similar measures • Discriminant validity • Relation to other dissimilar measures • Criterion validity • Ability of measure to predict clinical outcome
Analyses • Between group (continuous DV*) * IV = Independent variable = manipulated or controlled variable * DV = Dependent variable = variable that we measure
Analyses • Between group (continuous DV) * IV = Independent variable = manipulated or controlled variable * DV = Dependent variable = variable that we measure
Analyses • Correlation • Pearson’s r • Strength of relationship between two continuous variables • e.g., relation between self-efficacy and readiness for change • Multiple regression • Strength of relationship between multiple IVs and one DV • e.g., relation between self-efficacy, distress, shape and weight-based self-esteem, and readiness for change
Analyses • Categorical variables • Mann-Whitney U (T-test) • Comparing dropout between RMT and non-RMT participants • Kruskal-Wallis (ANOVA) • Comparing dropout between RMT, non-RMT, and psychoeducation participants • Phi Coefficient (Correlation) • Relation between martial status and dropout • Logistic regression (Regression) • Predicting who will decide to enrol in treatment from level of readiness to change
Conclusions • Common errors: • Overgeneralizing the results • Overstating the significance of findings • Concluding causality