Single‐case research designs have primarily relied on visual analysis for determining treatment effects. However, current foci on evidence‐based treatment have given rise to the development of new methods. This article presents descriptions, calculations, strengths and weaknesses, and interpretative guidelines for 5 effect size indices: the percent of nonoverlapping data, the percent of data exceeding the median, improvement rate difference, nonoverlap of all pairs, and Tau‐U.

Visual analysis is the most widely applied method of data interpretation for single-case research as it encompasses multifaceted considerations relevant to evaluating behavior change. However, a previous research synthesis found low levels of interrater agreement between visually analyzed ratings of graphed data across all variables under analysis. The purpose of this meta-analysis was to evaluate the peer-reviewed literature to date for potential moderators affecting the proportion of interrater agreement between visual analysts. Nineteen articles with 32 effects were assembled. Potential moderators evaluated included (a) design families, (b) rater expertise, (c) the provision of contextual information for graphs, (d) the use of visual aids, (e) the provision of an operational definition of the construct being rated, and (f) rating scale ranges. Results yielded an overall weighted interrater agreement proportion of .76. Moderator variables identified produced low to adequate levels of interrater agreement. Practical recommendations for future research are discussed.

No abstract

Antecedent physical exercise has emerged as a potentially promising treatment for reducing challenging behavior and increasing academic behavior in individuals with autism spectrum disorder (ASD). The purpose of this study was to evaluate the effects of physical exercise conducted prior to instructional sessions (antecedent physical exercise) on academic engagement and stereotypy during instructional sessions for two children diagnosed with ASD. Functional analysis results suggested stereotypy was maintained by automatic reinforcement for both participants. A multielement design was employed to evaluate academic engagement and stereotypy during instructional sessions following randomly sequenced conditions involving either (a) no antecedent exercise, (b) brief durations of antecedent exercise, or (c) antecedent exercise that continued until the participant engaged in a systematically determined behavioral indicator of satiation. Both participants demonstrated higher levels of academic engagement and reduced levels of stereotypy during the instructional sessions which followed antecedent physical exercise that continued until behavioral indicators of satiation occurred. This study replicates previous research suggesting that individuals with ASD may benefit from physical exercise prior to academic instruction and further suggests that the duration of antecedent exercise may be optimally individualized based on behavioral indicators of satiation.

No abstract