Abstract
This article describes and field-tests the improvement rate difference (IRD), a new effect size for summarizing single-case research data. Termed “risk difference” in medical research, IRD expresses the difference in successful performance between baseline and intervention phases. IRD can be calculated from visual analysis of nonoverlapping data, and is easily explained to most educators. IRD entails few data assumptions and has confidence intervals. The article applies IRD to 166 published data series, correlates results with three other effect sizes: R2, Kruskal-Wallis W, and percent of nonoverlapping data (PND), and reports interrater reliability of the IRD hand scoring. The major finding is that IRD is a promising effect size for single-case research.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
