Analysis of Effect for Single-Case Design Research

Single-case design (SCD) research is an experimental approach for analysis of an effect between an independent variable and dependent variable. Traditionally, analysis of effect for SCD has relied on visual analysis, an approach whereby a trained observer analyzes a visual display of the data. Recent advances in statistical approaches have been forwarded for SCD research in the literature to assist in the interpretation of intervention effects. This review outlines the logic of SCD and describes the varied approaches for the analysis of effect in SCD research.     

Bottom-Up Analysis of Single-Case Research Designs

This paper defines and promotes the qualities of a ??bottom-up?? approach to single-case research (SCR) data analysis. Although ??top-down?? models, for example, multi-level or hierarchical linear models, are gaining momentum and have much to offer, interventionists should be cautious about analyses that are not easily understood, are not governed by a ??wide lens?? visual analysis, do not yield intuitive results, and remove the analysis process from the interventionist, who alone has intimate understanding of the design logic and resulting data patterns. ??Bottom-up?? analysis possesses benefits which fit well with SCR, including applicability to designs with few data points and few phases, customization of analyses based on design and data idiosyncrasies, conformation with visual analysis, and directly meaningful effect sizes. Examples are provided to illustrate these benefits of bottom-up analyses.     

The Analysis of Single-Case Research Data: Current Instructional Practices

Visual analysis is the predominant method of analysis in single-case research (SCR). However, most research suggests that agreement between visual analysts is poor, which may be due to a lack of clear guidelines and criteria for visual analysis, as well as variability in how individuals are trained. We developed a survey containing questions about the content and methods used to teach visual and statistical analysis of SCR data in verified course sequences (VCS) and distributed it via the VCS Coordinator Listserv. Thirty-seven instructors completed the survey. Results suggest that there is variability across instructors in some fundamental aspects of data analysis (e.g., number of effects required for a functional relation) but a great deal of consistency in others (e.g., emphasizing visual over statistical analysis). We discuss our results along with their implications both for teaching students to analyze SCR data and for conducting additional research on behavior-analytic training programs.

     

Meta-Analysis of Single-Case Design Research on Self-Regulatory Interventions for Academic Performance

The current study examined the effects of self-regulatory interventions on reading, writing, and math by conducting a meta-analysis of single-case design research. Self-regulatory interventions have promise as an effective approach that is both minimally invasive and involves minimal resources. Effects of the interventions were analyzed by academic subject, grade, educational placement, and the number of sessions. Results indicated that self-regulatory strategies showed promise in addressing academic issues in the areas of reading, writing, and math regardless of age, grade, educational placement, and intervention length.     

Meta-Analysis of Single-Case Design Research: Introduction to the Special Issue

Single-case design (SCD) research focuses on finding powerful effects, but the influence of this methodology on the evidence-based practice (EBP) movement is questionable. Meta-analytic procedures may help facilitate the role of SCD research in the EBP movement, but meta-analyses of SCDs are controversial. The current article provides an introduction to the special issue on meta-analyses of SCD research by discussing concerns regarding the internal and external validity of these designs. Specific considerations for increasing the validity of SCD meta-analyses are provided, as are brief overviews of the articles included in the special issue.     

Synthesizing Single-Case Research to Identify Evidence-Based Practices: Some Brief Reflections

The purposes of this paper are to (a) propose an operational standard for defining a ??practice,?? (b) encourage development of professional standards for visual and statistical analysis of single-case research, and (c) propose a standard for using single-case research results to identify practices that are ??evidence-based.?? These topics are not new for behavioral researchers, but they become critical for the larger conversations now occurring among researchers, policy makers, and educators working to implement effective practices in psychology and education.     

Examining Estimates of Effect Using Non-Overlap of All Pairs in Multiple Baseline Studies of Academic Intervention

The inclusion of single-case design (SCD) studies in meta-analytic research is an important consideration in identifying effective evidence-based practices. Various SCD effect sizes have been previously suggested; non-overlap of all pairs (NAP) is a recently introduced effect size. Preliminary field tests investigating the adequacy of NAP are promising, but no analyses have been conducted using only multiple baseline designs (MBDs). This preliminary study investigated typical values of NAP in MBDs, investigated agreement with visual analysis, and suggested cut scores for interpreting a NAP effect size. Typical values of NAP in MBDs were larger compared to a previous meta-analysis of studies using AB, MBD, or ABAB withdrawal designs, and agreement of suggested cut scores and visual analysis was moderate.     

Single-Case Experimental Designs in Family Therapy Research: Limitations and Considerations

Recent authors have encouraged the use of single-case experimental design in family therapy research. However, several issues related to the application of these designs have not been addressed. The present article suggests that the applicability of single-case methods to family therapy research may be limited. The first issue raised is the general lack of adequate dependent measures of family interaction that fulfill the requirements of the single-case experimental designs. Suggestions for development of appropriate measures are given. Second, the necessary reliance on relatively weak single-case designs often allows only relatively weak conclusions. Finally, the strategy of beginning the single-case study of family functioning and family therapy in laboratory settings is suggested.     

A Comparison of Rubrics for Identifying Empirically Supported Practices with Single-Case Research

The use of single-case research methods for validating academic and behavioral interventions has gained considerable attention in recent years. As such, there has been a proliferation of methods for evaluating whether, and to what extent, primary research reports provide evidence of intervention effectiveness. Despite the recent interest in harnessing single-case research to identify empirically supported strategies, examination of these tools has revealed that there is a lack of consistency in the methodological criteria sampled and scoring procedures used to evaluate primary research reports. The present study examined the extent to which various evidence rubrics addressed specific methodological features of single-case research and classified studies into similar evidence categories. Results indicated that the methodological criteria included within rubrics tended to vary, particularly for criteria related to determining the generality of the intervention under study. Moreover, there was substantial discordance observed in the evidence classifications assigned to reviewed studies. These findings are discussed in the context of the still-developing nature of single-case evidence reviews. Recommendations for both research and practice are provided.     

Advocates for All Students: An American Right

The question of advocates for students in public schools has generated diverse responses. Administrators may believe that an unnecessary adversarial relationship will be encouraged by an outside advocacy organization. Yet, administrators polled for this study estimated that as many as 50% of students may not have advocates, and the advocates of an additional 25% are relatively unskilled in their advocacy attempts. Considering that the presence of advocates has been shown to increase student retention and academic success, it seems imperative that exemplary programs be identified and modeled throughout our public school system.     

心理学实验研究的效果大小

从"心理学实验数据处理"的角度,我们可以把"效果大小"理解为"是指在心理学实验报告中反映‘自变量’对‘因变量’所产生的影响有多大的统计指标"。这一统计指标需要在掌握"虚无假设分布"和"备择假设分布"这两个抽样分布原理的基础上才能得以准确的理解,并因此知道我们在"对心理学实验数据处理过程中通过假设检验进行推断统计"之后报告研究结果时为什么需要使用这一指标。心理学实验数据处理过程中使用不同的检验方法具有与该方法相应的不同的效果大小指标,每一种检验方法也可以使用不同的指标来反映其实验处理的效果大小。对此,就"心理统计学"提到的四种主要假设检验方法所得推断结果应该使用何种"效果大小"指标更为合适提出了我们的建议。     

Effect Size Strengths in Subjective Well-Being Research

Subjective well-being (SWB) research is characterized by many large samples, which often results in virtually all variables being significantly related to well-being, even if the associations are small. In this article we explore the strengths of associations between various predictors and SWB outcomes. In addition to standard effect-size statistics, we also examined the range of the SWB scale covered in the distribution of the predictor, allowing us to estimate the strength of influence of each variable, independent of variability in the sample. We analyzed just a few variables to illustrate what our approach reveals. Our analyses included a representative sample of both the world and the United States, and our data included three types of SWB (life satisfaction (LS), positive affect (PA), and negative affect (NA)). The largest effect sizes emerged for societal characteristics, such as between-nations differences, as well as personal characteristics, such as perceived social support. Small or very small effect sizes were consistently found for demographic characteristics, such as sex, age, and marital status. Other effect sizes varied by the type of SWB being considered. For example, income resulted in a large effect size for LS, but small to medium effect sizes for PA and NA. We suggest that when scholars report and interpret the associations of predictor variables with SWB, they consider the strengths of their significant associations.

     

Brief Experimental Analysis of Written Letter Formation: Single-Case Demonstration

Many students experience difficulty in acquiring basic writing skills and educators need to efficiently address those deficits by implementing an intervention with a high likelihood for success. The current article demonstrates the utility of using a brief experimental analysis (BEA) to identify a letter-formation intervention for a second-grade student with handwriting difficulties. The results suggested that the BEA led to differentiated results for letter formation interventions, and the identified intervention was implemented for 8 weeks with moderate effectiveness. Suggestions for future research are included.     

Pairs for Pairs: A Theoretical Base for Co-Therapy as a Nonsexist Process in Couple Counseling

A synthesis of contemporary literature provides a theoretical base for female-male co-therapy teams as the most likely modality to mediate sex bias in couple counseling.     

Sample Size Planning for Detecting Mediation Effects: A Power Analysis Procedure Considering Uncertainty in Effect Size Estimates

Abstract

When planning mediation studies, researchers are often interested in the sample size needed to achieve adequate power for testing mediation. Power depends on population effect sizes, which are unknown in practice. In conventional power analysis, effect size estimates, however, are often used as population values, which could result in underpowered studies. Uncertainty in effect size estimates has been considered in other sample size planning contexts (e.g., t-test, ANOVA), but has not been handled properly for planning mediation studies. In the current study, we proposed an easy-to-use sample size planning method for testing mediation with uncertainty in effect size estimates considered. We conducted simulation studies to demonstrate the impact of uncertainty in effect size estimates on power of testing mediation, and to provide sample size suggestions under different levels of uncertainty. Empirical examples were provided to illustrate the application of our method. R functions and a web application were developed to facilitate implementation.     

A cognitive-linguistic intervention model for mother-infant Pairs: Birth-to-three

There is a challenge to develop an educational technology which promotes cognitive and linguistic competency among children of the poor. Researchers who have studied early interactions between mother and child and service deliverers who have implemented parenting programs recognize the link between cognitive and language development. The focus of this paper is a curriculum model which includes both areas of development. The interactive behaviors of mother and child during three successive stages of the child's development (0–9 months, 9–18 months, and 18–36 months) from the matrix of the cognitive-linguistic intervention model.     

The Use of Single-Case Experimental Research to Examine Physical Activity,Exercise, and Physical Fitness Interventions: A Review

This review identified studies that have utilized single-case experimental methods to evaluate physical activity, exercise, and physical fitness interventions. A total of 10 studies met the inclusion criteria. Single-case experimental design studies were inclusive to clinical populations and able to demonstrate an intervention effect. Future researchers should use validated and reliable assessments of physical activity or physical activity capacity, establish stable baseline assessments of their target behavior prior to the introduction of any intervention, use statistical tests to establish clinical and statistical significance, and move away from simple A-B designs that do not rule out the effects of extraneous variables.