Comparison of dual discrepancy criteria to assess response to intervention Matthew K. Burns a, * , Barbara V. Senesac b a University of Minnesota, USA b Central Michigan University, USA Received 23 August 2005; received in revised form 24 August 2005; accepted 21 September 2005 Abstract Much of the research regarding diagnosing children as LD with responsiveness-to-intervention (RTI) has examined methods to identify children as non-responsive. The current study examined the dual discrepancy (DD) definition in which children score low on a post-intervention reading measure and score below their peers in reading growth rates. Four definitions of DD were compared, student growth below the 25th percentile, 33rd percentile, 50th percentile, and less than one standard deviation below the mean. Participants were 151 children in grades 1 through 3 who were identified as experiencing reading difficulties. Results suggested that the three percentile groups significantly differentiated reading scores between DD and non-DD children, but the one standard deviation group did not. No ethnic or gender biases were noted and the 25th and 33rd percentile criteria closely matched estimates of LD prevalence. Implications for future research are included. D 2005 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved. Keywords: Dual discrepancy; RTI; Response to intervention; Reading assessment Educators have a long history of fascination with that which is new and tended to adopt new ideas before they were supported with research (Ellis, 2001). The No Child Left Behind mandate for evidence-based practices should diminish the practice of fanfare taking priority over research, but substantive mind-set changes take time. Special education is a field that 0022-4405/$ - see front matter D 2005 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.jsp.2005.09.003 * Corresponding author. E-mail address: burns258@umn.edu (M.K. Burns). Journal of School Psychology 43 (2005) 393 – 406