EBP Week 7

Single-Subject Research (SSR)

• SSR is a research design studying one participant intensely, using repeated measurements during baseline, intervention, and post-treatment.
• SSR allows the participant to act as their own control.

A, B, C Designations in SSR

• A, B, C designations are notations describing phases of an SSR study.
• Phase A signifies observation with measurement and designates baseline or treatment withdrawal phases.
• Phase B signifies intervention.
• Phases C, D, etc., signify comparison interventions.

Case Studies vs. SSDs

• Case studies report single-patient examples without controlled intervention manipulation.
• Case studies are typically retrospective and lack experimental controls, differing from SSDs.

RCTs with SSDs

• RCTs with SSDs implement randomized controlled trials using single-subject designs.
• Multiple single-subject studies are grouped, and participants are randomly assigned to different treatment conditions.

Celeration Line

• A celeration line is a "best-fit" line through data in an SSR study.
• It aids in visual interpretation of data trends across phases.

Two-Standard-Deviation Band

• Two-Standard-Deviation Band is a statistical test using the celeration line.
• It determines statistical significance in SSR data, assuming normal distribution and no significant autocorrelation.

Detrending Data

• Detrending data is removing the natural trend in the variable.
• It occurs during the baseline phase from subsequent treatment phases in SSDs.

Serial Dependency/Autocorrelation

• Serial dependency/autocorrelation is data dependency created by repeated measures on the same person.
• Autocorrelation should be analyzed for statistical significance.

Qualitative Research Focus

• Qualitative research focuses on questions of experience, culture, and social/emotional health.

Qualitative Research Designs

• Qualitative Research Designs include ethnography, phenomenology, grounded theory, biography, and case study.

Triangulation

• Triangulation involves using different perspectives or methods to study a process.
• Triangulation strengthens results in a qualitative study.

Member Checking

• Member checking verifies if an investigator has adequately represented a participant's contributions.

Qualitative Research Method

• Qualitative Research uses a rigorous approach to answer a descriptive research question with nonnumeric data and typically analyzes language to describe experiences and perceptions.

Interpretivist Approach

• The Interpretivist Approach assumes everything is filtered through socially mediated influences.
• Researchers acknowledge their influence on the research with the Interpretivist Approach

Positivist Approach

• Positivist Approach assumes study findings represent truth, similar to quantitative research.

Reflexivity

• Reflexivity includes the explicit acknowledgment of biases by researchers.
• Gender, relationship to participants, experience, and professional background are important factors.

Saturation

• Saturation is when no new information emerges during data collection.
• Saturation can determine when researchers stop collecting data.

Coding

• Coding involves breaking data into discrete units while grouping similar codes together to create meaning.

Single-Subject Research (SSR) Design: Core Concepts & Advantages

• SSR designs intensely focus on a single participant.
• Variables of interest (outcome measures) are repeatedly measured during baseline, intervention, and post-intervention.
• In a typical single-subject design (SSD), one participant is followed intensely.
• Before intervention, variables of interest are repeatedly measured during a baseline period.
• SSR results are more directly applicable to individual patients than those from randomized clinical trials (RCTs).
• This is especially true when the study participant is similar to the patient.
• Rigorous research with single participants can sometimes be applied more directly to patients than results from a group in an RCT.
• In SSR, the participant serves as their own control, reducing inter-subject variability.
• In an SSD, the subject acts as their own control.
• The participant’s baseline and intervention periods are compared to detect possible treatment effects.
• With RCT implementation using SSDs multiple single-subject studies are grouped together along with the participants who have similar characteristics.
• Subjects are randomly assigned to treatment conditions and protocols are standardized across subjects.
• Multiple measures are obtained on each subject, documenting fluctuations of the outcome of interest during phases of no treatment to provide insight into response variability.
• In RCT with Crossover participants are randomly assigned to a treatment and switched to an alternative treatment.

Distinguishing SSR from Case Studies

• SSR designs feature controlled, single-subject experimental designs with systematic control, implementation, and evaluation of treatment.
• Case studies are retrospective and descriptive, lacking controlled experimental manipulation.
• Case studies differ from an SSD because they are typically written retrospectively.
• Case studies detail the characteristics of one case and the course of intervention, thus a case study is not considered a controlled singlesubject experimental design.

Common SSR Designs (with Notation)

• A-B: Baseline (A) followed by intervention (B) is appropriate when other "events" aren't expected to affect the treatment outcome during baseline.
• A-B-A: Baseline (A), intervention (B), and return to baseline/withdrawal (A) is suitable if a treatment can be withdrawn.
• A-B-A-B: Baseline (A), intervention (B), withdrawal (A), and reintroduction of intervention (B) determine the full effects of treatment.
• A-B-A-C-A: Baseline (A), intervention (B), withdrawal (A), a second intervention (C) in combination with the first treatment, then a return to baseline.
• The following letters are used to designate phases of a single-subject research (SSR) study: A = Phase of observation with measurement.
• The following letters are used to designate phases of a single-subject research (SSR) study: B = Intervention.
• The following letters are used to designate phases of a single-subject research (SSR) study: C, D, etc. = Comparison interventions.

Appraising SSR Quality & Applicability

• Is its purpose relevant to the clinical question, and is the participant similar enough to the patient?
• Are outcome measures relevant and clinically realistic, and were measures taken repeatedly during baseline to capture natural fluctuations?
• Was blinding/masking optimized?
• Is the intervention clinically realistic, and were other events monitored to rule out their contribution to the outcome?
• Were both visual (graphs, celeration lines) and statistical analyses applied, and were data trends in the baseline removed from intervention data (detrending)?
• Are the outcomes clinically important and meaningful to the patient?

Analysis of Results

• Visual inspection determines and describes trends in data.
• Trend-line analysis, such as the celeration line, assists in describing increasing and decreasing trends in the data.
• SSD uses specific statistics that draw upon different assumptions than statistics for group designs.
• "Detrending data and serial dependency" refers to how repeated measures on the same person create dependency in the data.
• If autocorrelation values remain significant, further statistical analysis will be problematic.
• The Two-Standard-Deviation band is used in combination with the celeration line.
• Following convention, if two data points are above or below the 2SD bands in the treatment phase, the change is considered statistically significant.

Core Concepts & Purpose of Qualitative Research

• It focuses on questions of experience, culture, and social/emotional health to understand processes experienced by individuals or groups.
• Qualitative research focuses on questions of experience, culture, and social/emotional health.
• The generation of hypotheses is often used rather than testing pre-defined ones.
• One purpose is to generate hypotheses, in contrast to quantitative research in which pre-stated hypotheses are tested.
• Non-Numeric Data analyses non-numeric data, like the language used by participants.
• Philosophical assumptions influence what is valued and how data are analyzed plus researchers should include information about the philosophical basis in the methods section.
• Words are most commonly used as content, such as when organized and coded into themes.
• Methods using words in this way include thematic analysis and grounded theory.

Qualitative vs. Quantitative Research (Key Differences)

• Qualitative: Hypothesis generating, understanding experiences.
• Quantitative: Hypothesis testing, establishing causal relations.

Common Qualitative Designs

• Phenomenology studies lived experiences, such as studying the life experience of depression.
• Ethnography studies group behavior, culture, and beliefs, such as studying factors related to living and aging with HIV comorbidities for African American women.
• Grounded Theory constructs or validates a theory based on core processes in a life experience, such as studying the use of electric wheelchairs.

Appraising Qualitative Research

• Examine the relevance to the clinical question.
• Note whether a qualitative approach was appropriate for the research question.
• Identify whether the sampling strategy was clearly defined and justified (Purposeful, snowball sampling).
• Scrutinize data collection methods (interviews, focus groups) and whether information was recorded.
• Assess data analysis methods (coding, thematic analysis) plus if the results are credible and address the research question.
• See if results justify the conclusions and if alternative explanations have been explored and The results of a qualitative study in light of the study's overall purpose.

Reflexivity

• Explicit acknowledgment of biases.
• Important factors might include gender, relationship to participants, experience, and professional background.

Implications for Evidence-Based Practice

• Both SSR and qualitative research provide valuable insights that complement traditional group designs (RCTs).
• The choice of research design should align with the nature of the research question.
• Qualitative research provides rich insights into patient experiences that may not be accessible through quantitative methods.
• SSR can help measure the effects of treatment with a specific patient.
• Appraisal of these alternative designs requires considering specific quality criteria and analysis methods tailored to their unique characteristics.

Key Themes

• Alternative study designs include research and non-research approaches.
• Research designs, such as quasi-experimental studies and single-subject designs, start with a clinical question and apply the scientific method.
• Non-research designs, including case studies and case series, typically involve an interesting or unusual clinical situation where a clinician treats a patient and reports the outcomes.

Single-Subject Designs (SSD)

• SSDs involve collecting numerous data points on one or more individuals.
• Instead of aiming for a representative sample of a large population, SSDs focus on obtaining extensive data from a few individuals.
• SSDs often require fewer resources than randomized controlled trials (RCTs) because of fewer visits, even with more data points.
• Multiple data points in SSDs can reveal trends and patterns, offering a better picture of clinical outcomes compared to few data points prone to errors.
• Multiple baseline measurements in SSDs help detect natural variations in clinical outcome scores and better determine the minimal detectable change for an individual.
• Different statistical analyses are used for single-subject designs compared to RCTs to focus on trends instead of individual time point differences.
• SSD notation uses letters to designate phases, where 'A' represents baseline or treatment withdrawal and 'B' represents intervention.

Crossover Designs summary

• In a crossover design, all participants receive both the treatment and the control (or placebo) and the order can be varied.
• Crossover designs include a washout period between treatments to minimize carryover effects from the first treatment.
• Crossover studies involve multiple visits for each patient and may be combined with single-subject designs.

Quasi-Experimental Designs

• Quasi-experimental designs involve a treatment group and a control group but do not have random assignment.
• This way the cause and effect relationship can be difficult to establish.

Qualitative Research explanation

• Qualitative research explores experiences, culture, and social/emotional health, focusing on understanding processes.
• Qualitative research uses nonnumeric data. Qualitative research designs include phenomenology, ethnology, and grounded theory.
• Phenomenology studies lived experiences.
• Ethnology explores group behavior, attitudes, and beliefs.
• Grounded theory constructs or validates a theory.

Appraising Single-Subject Research (SSR)

• Appraising the applicability and validity of SSR follows similar guidelines to group designs, but with modifications for the smaller number of participants and specific statistical analysis.
• Key questions include study's relevance, participant's similarity to the patient, and the relevance of outcome measures.

Visual and Statistical Analyses in SSR

• Analysis of single-subject studies should include visual inspection and statistical analysis.
• Visual inspection involves determining trends in data using methods like trend-line analysis and celeration lines.
• Statistical analysis for SSDs uses statistics that account for serial dependency of data.

Qualitative vs. Quantitative Research differences

• Qualitative research generates hypotheses and explores life experiences.
• Quantitative research tests hypotheses and establishes causal relations.
• Qualitative research uses purposive sampling with small sample sizes.
• Quantitative research uses random sampling with larger sample sizes.
• Reflexivity explicitly acknowledges biases.
• Triangulation is the use of different perspectives to study an identified process used in both types of studies.
• Member checking verifies that the investigator has adequately represented the participant’s contributions.