Lecture OverviewProblems With Traditional Group DesignsSlide 3Labels Used to Describe Time Series DesignsAdvantages of Time Series DesignsWhy Don’t Clinicians Use Time Series Designs More Frequently?Major Elements of Time Series DesignsImportant Parameters of Time Series DataMethods for Handling InstabilityBaseline TrendsExamples of BaselinesSlide 12Slide 13Slide 14Slide 15Slide 16Slide 17Major Classes of Time Series DesignsExample of the Controlled Case Study DesignFactors Important in the Evaluation of Case StudiesSlide 21Example of the A-B-A Withdrawal DesignExample of the A-B-A-B Withdrawal DesignFeatures of Withdrawal DesignsSlide 25Variants of Withdrawal DesignsSlide 27Features of the Multiple Baseline DesignSlide 29Features of the Alternating Treatment DesignSlide 31Example of a Multiple Baseline Design Across SubjectsSlide 33Slide 34Example of a Multiple Baseline Design Across BehaviorsSlide 36Slide 37PowerPoint PresentationAdvantages of the Multiple Baseline DesignSlide 40Slide 41Advantages of the Alternating Treatment DesignClinical Applications (Idiographic Assessment)Example of Alternating Treatment DesignSlide 45Slide 46Slide 47Slide 48Lecture Overview•What are the limitations of traditional group designs?•What are time series designs?•What are the advantages and limitations of time series designs?•What are the different types of time series designs and examples of their application?Problems With Traditional Group Designs•Practical problems associated with requiring large groups of subjects•Ethical concerns about no-treatment controls•Inability to generalize the findings from group means to the individual caseProblems With Traditional Group Designs•Not suited for the treatment evaluation of a single case•Has contributed to the dichotomy of researcher vs. practitionerLabels Used to Describe Time Series Designs•Single-subject designs•N of one designs•Intensive designsAdvantages of Time Series Designs•Uniquely suited for evaluation of treatment for a single case (goodness of fit)•Can be used to test treatments of rare disorders that would not lend themselves to traditional group designs•Avoids the legal and ethical problems associated with withholding treatment (control groups)•Well-suited for studying process of change•Provides options for practitioners to be researchersWhy Don’t Clinicians Use Time Series Designs More Frequently? •Not taught in many training programs•Not aimed at the practicing clinician•They are associated with behaviorism•Few outlets for single-case clinical research•Clinical agencies fail to provide support for scientific workMajor Elements of Time Series Designs•Use of repeated measurements•Variability is assessed across time•Independent and dependent variables are carefully specified while other variables are held constant•Employ a flexible format that can be altered midstream•Use “replication of effect” to establish internal validity*Important Parameters of Time Series Data•Level (Intercept)•Slope (trend)•VariabilityMethods for Handling Instability•Analyze sources of variability•Wait for a more stable pattern to emerge•Examine the temporal unit of analysis•Proceed despite the variabilityBaseline Trends•StableExamples of BaselinesStable Baseline30801301800 1 2 3 4 5 6DAYSNo. of Vocal TicsBaseline Trends•Stable•AscendingExamples of BaselinesAscending Baseline30801301800 1 2 3 4 5 6DAYSNo. of Vocal TicsBaseline Trends•Stable•Ascending•*DescendingExamples of BaselinesDescending Baseline501001502000 1 2 3 4 5 6DAYSNo. of Vocal TicsBaseline Trends•Stable•Descending (worsening)•*Ascending (improving)•*UnstableExamples of BaselinesVariable Baseline30801301802300 1 2 3 4 5 6DAYSNo. of Vocal TicsMajor Classes of Time Series Designs•Controlled case study–Data are collected on one or more individuals during a baseline (pretreatment) phase AND during a treatment/intervention phase.–Does not control for many threats to validityExample of the ControlledCase Study DesignIncreasing Classroom Attending10305070901105 9 15 20No. of 10-min. Observation SessionsPercent Attending BehaviorWalker, H.M., & Buckley, N.K. The use of positive reinforcement in conditioning attending behavior. Journal of Applied Behavior Analysis, 1968, 1, 245-250Baseline Reinforcement ContingencyFactors Important in the Evaluation of Case Studies •Type of data•Assessment occasions•Past and future projections•Type of effect•Number and heterogeneity of subjects•Treatment integrityMajor Classes of Time Series Designs•Withdrawal (Reversal) designs–A/B/A–A/B/A/B–A/B/B+C/B/B+CExample of the A-B-A Withdrawal DesignIncreasing Classroom Attending10305070901105 9 15 20 25 30 35No. of 10-min. Observation SessionsPercent Attending BehaviorWalker, H.M., & Buckley, N.K. The use of positive reinforcement in conditioning attending behavior. Journal of Applied Behavior Analysis, 1968, 1, 245-250Baseline Reinforcement Contingency ExtinctionExample of the A-B-A-B Withdrawal DesignReducing In-Class Talking Out0123455 9 13 17SessionsNo. of Talk-outsHall, R.V., et al The teacher as observer and experimenter in the modification of disputing and talking-out behaviors. Journal of Applied Behavior Analysis, 1971, 4, 141-149.BaselineContingentAttentionContingentAttentionBaseline 2Features of Withdrawal Designs•Primary strategy involves the systematic introduction and withdrawal of treatment•Experimental control (internal validity) is demonstrated by showing that the target behavior changes as a function of the change in condition (phase change)•Particularly well-suited for treatments involving environmental change strategiesFeatures of Withdrawal Designs•Not well-suited for treatments that exert an enduring effect•Ethical and practical limitations associated with the withdrawal of treatmentVariants of Withdrawal Designs•Interactive (Component Analysis)–B/B+C/B/B+C–C/C+B/C/C+B–B+C/C/B+C/C•Comparing two or more treatments–A/B/A/C/A–A/C/A/B/AMajor Classes of Time Series Designs•Multiple baseline designs–Across subjects–Across behaviors–Across settingsFeatures of the MultipleBaseline Design•Similar in structure to the controlled case study•Involves the sequential introduction of treatment (phase change) across either multiple subjects, multiple target behaviors (symptoms), or multiple settingsFeatures of the MultipleBaseline Design•Demonstrates experimental
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