Journal of Learning Disabilities recent issues

The Role of the Teacher in Identifying Learning Disabilities: A Study Using the McCarney Learning Disability Evaluation Scale (LDES)

Souroulla, A. V., Panayiotou, G., Kokkinos, C. M. — Mon, 02 Nov 2009 14:32:45 PST

The purpose of the study was to examine whether the Greek translation of the Learning Disability Evaluation Scale (LDES) can be used in the identification of learning disabilities. The LDES was completed by 165 teachers for one of their students, aged 5 to 14 years. The LDES was significantly correlated to students’ grades in Math and Greek Language and to the Reading Ability Test. Scores on LDES from the above randomly selected sample were significantly different from scores on LDES for another sample of 47 students, who were manifesting learning disabilities, indicating that the LDES can distinguish between the two samples. The exploratory factor analysis revealed that the LDES maintains the original factor structure and the reliability values supported its internal consistency. Results and limitations are discussed.

College Students With Learning Disability Diagnoses: Who Are They and How Do They Perform?

Sparks, R. L., Lovett, B. J. — Mon, 02 Nov 2009 14:32:45 PST

The purpose of this study is to provide an up-to-date review of the literature on postsecondary students classified as having learning disabilities (LD). The review focused on the criteria by which students were classified as LD and the cognitive and achievement characteristics of the participants. From almost 400 studies, only 30% were empirical (data-based) investigations reporting original data. Findings showed that a wide range of criteria was used to classify students as LD, although various discrepancy criteria and registration with university offices of disability services were most often cited. Participants’ mean scores on standardized intelligence and achievement tests were in the average range but somewhat lower than those of other college students. Generally, the findings show a lack of consensus among diagnosticians and researchers about how LD should be diagnosed and also show that college students classified as LD tend to have average achievement, despite scoring below their classmates.

Adult Dyslexia and Attention Deficit Disorder in Finland--Project DyAdd: WAIS-III Cognitive Profiles

Laasonen, M., Leppamaki, S., Tani, P., Hokkanen, L. — Mon, 02 Nov 2009 14:32:45 PST

The project Adult Dyslexia and Attention Deficit Disorder in Finland (Project DyAdd) compares adults (n = 119, 18—55 years) with dyslexia, attention-deficit/hyperactivity disorder (ADHD), dyslexia together with ADHD (comorbid), and healthy controls with neuropsychological, psychophysical, and biological methods. The focus of this article is on the Wechsler Adult Intelligence Scale—Third Edition (WAIS-III). The clinical groups performed well compared to the norms, and they did not differ from each other. However, compared to the controls, all of them were slightly poorer in their Full IQ, and of the factors, processing speed was relatively difficult for all of them. In addition to the group comparisons, a cluster analysis based on subtest scores was conducted over the clinical groups. It did not suggest a solution that would differentiate between the clinical groups. Instead, four clusters emerged: above average, average, poor perceptual organization, and poor working memory. Thus, differentiating between these clinical groups with the WAIS-III was not possible. However, all of them shared a relative difficulty in processing speed, and group-independent clusters with perceptual or memory difficulties emerged.

Investigating the Double-Deficit Hypothesis in Greek: Findings From a Longitudinal Study

Papadopoulos, T. C., Georgiou, G. K., Kendeou, P. — Mon, 02 Nov 2009 14:32:45 PST

This study examined longitudinally the double-deficit hypothesis in Greek, an orthographically consistent language, following a group of children from kindergarten to Grade 2. Four groups were formed on the basis of two composite scores of phonological and naming-speed criterion measures: a double-deficit group (DD; n = 17), a phonological deficit group (PD; n = 33), a naming deficit group (ND; n = 33), and a control group exhibiting no deficits (CnD; n = 159). The four groups were identified in Grade 1, and they were compared retrospectively in kindergarten only on the criterion measures, and in Grades 1 and 2 on measures of word-reading fluency and accuracy, orthographic processing, and passage comprehension. The effects of verbal and nonverbal ability, age, gender, and parental education were controlled among the groups. Results showed that the DD group exhibited greater dysfunction in reading and orthographic processing compared to the single-deficit and CnD groups. Also, although the three deficit groups were not easily differentiated in kindergarten, their differences were maximized in Grade 1 and retained in Grade 2. The type and severity of reading deficits found in the ND group were mostly associated with naming speed at both the word- and text-reading levels, deficits that persisted across development. The PD group showed mostly deficient orthographic and poor decoding skills that improved across development. Implications of the findings for the double-deficit hypothesis in languages with transparent orthographies are discussed.

The Role of Working Memory and Fluency Practice on the Reading Comprehension of Students Who Are Dysfluent Readers

Swanson, H. L., O'Connor, R. — Mon, 02 Nov 2009 14:32:45 PST

The authors investigated whether practice in reading fluency had a causal influence on the relationship between working memory (WM) and text comprehension for 155 students in Grades 2 and 4 who were poor or average readers. Dysfluent readers were randomly assigned to repeated reading or continuous reading practice conditions and compared with untreated dysfluent and fluent readers on posttest measures of fluency, word identification, vocabulary, and reading comprehension. Three main findings emerged: (a) The influence of WM on text comprehension was not related to fluency training, (b) dysfluent readers in the continuous-reading condition had higher posttest scores than dysfluent readers in the other conditions on measures of text comprehension but not on vocabulary, and (c) individual differences in WM better predicted posttest comprehension performance than word-attack skills. In general, the results suggested that although continuous reading increased comprehension, fluency practice did not compensate for WM demands. The results were interpreted within a model that viewed reading comprehension processes as competing for a limited supply of WM resources that operate independent of fluency.

Still Wanted: Teachers With Knowledge of Language

Moats, L. — Wed, 12 Aug 2009 13:46:44 PDT

Why Elementary Teachers Might Be Inadequately Prepared to Teach Reading

Wed, 12 Aug 2009 13:46:44 PDT

Several national reports have suggested the usefulness of systematic, explicit, synthetic phonics instruction based on English word structure along with wide reading of quality literature for supporting development in early reading instruction. Other studies have indicated, however, that many in-service teachers are not knowledgeable in the basic concepts of the English language. They may be well versed in children’s literature but not know how to address the basic building blocks of language and reading. The authors hypothesized that one of the reasons for this situation is that many instructors responsible for training future elementary teachers are not familiar with the concepts of the linguistic features of English language. This hypothesis was tested by administering a survey of language concepts to 78 instructors. The results showed that even though teacher educators were familiar with syllabic knowledge, they performed poorly on concepts relating to morphemes and phonemes. In a second study, 40 instructors were interviewed about best practices in teaching components and subskills of reading. Eighty percent of instructors defined phonological awareness as letter-sound correspondence. They also did not mention synthetic phonics as a desirable method to use for beginning reading instruction, particularly for students at risk for reading difficulties. In conclusion, providing professional development experiences related to language concepts to instructors could provide them the necessary knowledge of language concepts related to early literacy instruction, which they could then integrate into their preservice reading courses.

Professional Development in Scientifically Based Reading Instruction: Teacher Knowledge and Reading Outcomes

Podhajski, B., Mather, N., Nathan, J., Sammons, J. — Wed, 12 Aug 2009 13:46:44 PDT

This article reviews the literature and presents data from a study that examined the effects of professional development in scientifically based reading instruction on teacher knowledge and student reading outcomes. The experimental group consisted of four first- and second-grade teachers and their students (n = 33). Three control teachers and their students (n = 14), from a community of significantly higher socioeconomic demographics, were also followed. Experimental teachers participated in a 35-hour course on instruction of phonemic awareness, phonics, and fluency and were coached by professional mentors for a year. Although teacher knowledge in the experimental group was initially lower than that of the controls, their scores surpassed the controls on the posttest. First-grade experimental students’ growth exceeded the controls in letter name fluency, phonemic segmentation, nonsense word fluency, and oral reading. Second-grade experimental students exceeded controls in phonemic segmentation. Although the teacher sample was small, findings suggest that teachers can improve their knowledge concerning explicit reading instruction and that this new knowledge may contribute to student growth in reading.

How Teachers Would Spend Their Time Teaching Language Arts: The Mismatch Between Self-Reported and Best Practices

Cunningham, A. E., Zibulsky, J., Stanovich, K. E., Stanovich, P. J. — Wed, 12 Aug 2009 13:46:44 PDT

As teacher quality becomes a central issue in discussions of children’s literacy, both researchers and policy makers alike express increasing concern with how teachers structure and allocate their lesson time for literacy-related activities as well as with what they know about reading development, processes, and pedagogy. The authors examined the beliefs, literacy knowledge, and proposed instructional practices of 121 first-grade teachers. Through teacher self-reports concerning the amount of instructional time they would prefer to devote to a variety of language arts activities, the authors investigated the structure of teachers’ implicit beliefs about reading instruction and explored relationships between those beliefs, expertise with general or special education students, years of experience, disciplinary knowledge, and self-reported distribution of an array of instructional practices. They found that teachers’ implicit beliefs were not significantly associated with their status as a regular or special education teacher, the number of years they had been teaching, or their disciplinary knowledge. However, it was observed that subgroups of teachers who highly valued particular approaches to reading instruction allocated their time to instructional activities associated with other approaches in vastly different ways. It is notable that the practices of teachers who privileged reading literature over other activities were not in keeping with current research and policy recommendations. Implications and considerations for further research are discussed.

A Literacy Tutoring Experience for Prospective Special Educators and Struggling Second Graders

Spear-Swerling, L. — Wed, 12 Aug 2009 13:46:44 PDT

This study examined the learning of teacher candidates taking a language arts course in a special-educator preparation program and that of the second graders they tutored in a supervised field component of the course. Teacher candidates’ knowledge of literacy instruction was assessed using five knowledge tasks; children were assessed on several measures of basic reading and spelling skills as well as on their knowledge of phonics concepts such as syllable types. Teacher candidates generally had inaccurate perceptions of their knowledge at pretest, but their knowledge improved significantly on all tasks after course instruction. Tutored children improved significantly from pre- to posttest on all assessments. The study suggests that carefully designed literacy coursework with field experiences can benefit both prospective special educators and struggling readers.

Teachers' Perception of Satisfaction, Skill Development, and Skill Application After Instructional Consultation Services

Kaiser, L., Rosenfield, S., Gravois, T. — Wed, 12 Aug 2009 13:46:44 PDT

A primary hypothesized outcome of consultee-centered consultation, including instructional consultation (IC), is that consultees will become more skilled. However, these claims have not been well researched. Data from 274 teachers implementing IC were analyzed to investigate perceptions of satisfaction and skill development. Results indicated that teachers were highly satisfied, perceived outcomes to meet or exceed their expectations, and felt confident about handling similar problems in the future. The majority reported learning one or more skills or strategies from participating and indicated generalization of skills learned from IC to other students. Relationships between satisfaction, generalization, and perceived outcomes are also presented. Although based on descriptive methodology, this analysis of teachers’ perceptions of IC provides a window into their experiences.

Do Textbooks Used in University Reading Education Courses Conform to the Instructional Recommendations of the National Reading Panel?

Wed, 12 Aug 2009 13:46:44 PDT

Two reasons may be responsible for the poor grasp of the linguistic concepts related to literacy acquisition by preservice and in-service teachers: a lack of attention given to such concepts by teacher educators (college faculty members) and a lack of relevant information provided in the textbooks used in college courses. In an earlier study, the authors found that many teacher educators involved in the training of preservice and in-service teachers were not well acquainted with these concepts. In this study, the authors examined the extent to which textbooks used in reading education courses contain the information about the five components of literacy instruction (phonemic awareness, phonics, fluency, vocabulary, and text comprehension) recommended by the National Reading Panel. Such scrutiny shows that many textbooks do not adequately cover these five components and the related instructional procedures for teaching them. In addition to the paucity of information about teaching the five components, some textbooks present inaccurate information.

Licensure Tests for Special Education Teachers: How Well They Assess Knowledge of Reading Instruction and Mathematics

Stotsky, S. — Wed, 12 Aug 2009 13:46:44 PDT

To determine the extent to which knowledge of evidence-based reading instruction and mathematics is assessed on licensure tests for prospective special education teachers, this study drew on information provided by Educational Testing Service (ETS), the American Board for Certification of Teacher Excellence, and National Evaluation Systems (now Evaluation Systems group of Pearson). It estimated the percentage of test items on phonemic awareness, phonics, and vocabulary knowledge and on mathematics content. It also analyzed descriptions of ETS’s tests of "principles of teaching and learning." Findings imply that prospective special education teachers should be required to take both a dedicated test of evidence-based reading instructional knowledge, as in California, Massachusetts, and Virginia, and a test of mathematical knowledge, as in Massachusetts. States must design their own tests of teaching principles to assess knowledge of evidence-based educational theories.

Teacher Knowledge, Instructional Expertise, and the Development of Reading Proficiency

Reid Lyon, G., Weiser, B. — Wed, 12 Aug 2009 13:46:44 PDT

Teacher knowledge and instructional expertise have been found in correlational and pre- and posttest studies to be related to student reading achievement. This article summarizes data presented in this special issue and additional research to address four questions: (a) What do expert reading teachers know? (b) Why do teachers need to acquire this knowledge? (c) Do teachers believe they have this knowledge? and (d) Are teachers being adequately prepared to teach reading? Well-designed studies relevant to this topic have been sparse with a noticeable lack of attention given to identifying specific causal links between teacher knowledge, teaching expertise, and student reading achievement. Until the appropriate research designs and methodologies are applied to address the question of causal effects, conclusions about the specific content that teachers must know and the instructional practices that are most beneficial in presenting this content are preliminary at best. Future studies of the effect of essential reading content knowledge must be extended beyond word-level skills to vocabulary, reading comprehension, and writing.

Enhancing the Reading Fluency and Comprehension of Children With Reading Disabilities in an Orthographically Transparent Language

Snellings, P., van der Leij, A., de Jong, P. F., Blok, H. — Fri, 12 Jun 2009 13:16:35 PDT

Breznitz (2006) demonstrated that Hebrew-speaking adults with reading disabilities benefited from a training in which reading rate was experimentally manipulated. In the present study, the authors examine whether silent reading training enhances the sentence reading rate and comprehension of children with reading disabilities and whether results found in Hebrew equally apply to an orthographically transparent language. Training results of 59 Dutch children with reading disabilities and normally achieving children show that children with reading disabilities are able to increase their sentence reading rate with high comprehension levels when pushed to do so with accelerated reading training. Posttest results show that transfer to routine reading is less strong for both accelerated and unaccelerated reading. Only accelerated training allows children with reading disabilities to read at high speed while maintaining high comprehension levels.

Five-Year Growth Trajectories of Kindergarten Children With Learning Difficulties in Mathematics

Morgan, P. L., Farkas, G., Qiong Wu, — Fri, 12 Jun 2009 13:16:35 PDT

The investigators used data from the Early Childhood Longitudinal Study—Kindergarten Cohort (ECLS-K) to estimate whether and to what extent the timing and persistence of mathematics difficulties (MD) in kindergarten predicted children's first through fifth grade math growth trajectories. Results indicated that children persistently displaying MD (i.e., those experiencing MD in both fall and spring of kindergarten) had the lowest subsequent growth rates, children with MD in spring only had the second-lowest growth rates, and children with MD in the fall only (and who had thus recovered from their MD by the spring of kindergarten) had the next-lowest growth rates. The children who did not have MD in either fall or spring of kindergarten had the highest growth rates. These results were observed prior to and after statistical control for additional variables. They indicate that measuring the timing and persistence of kindergarten children's mathematics learning difficulties may help identify those most at risk for failing to become mathematically proficient during elementary school.

Proofreading Using an Assistive Software Homophone Tool: Compensatory and Remedial Effects on the Literacy Skills of Students With Reading Difficulties

Lange, A. A., Mulhern, G., Wylie, J. — Fri, 12 Jun 2009 13:16:35 PDT

The present study investigated the effects of using an assistive software homophone tool on the assisted proofreading performance and unassisted basic skills of secondary-level students with reading difficulties. Students aged 13 to 15 years proofread passages for homophonic errors under three conditions: with the homophone tool, with homophones highlighted only, or with no help. The group using the homophone tool significantly outperformed the other two groups on assisted proofreading and outperformed the others on unassisted spelling, although not significantly. Remedial (unassisted) improvements in automaticity of word recognition, homophone proofreading, and basic reading were found over all groups. Results elucidate the differential contributions of each function of the homophone tool and suggest that with the proper training, assistive software can help not only students with diagnosed disabilities but also those with generally weak reading skills.

Emergent Literacy Intervention for Prekindergarteners at Risk for Reading Failure

Bailet, L. L., Repper, K. K., Piasta, S. B., Murphy, S. P. — Fri, 12 Jun 2009 13:16:35 PDT

This study examined the effectiveness of an assessment and intervention study targeting prekindergarten children at risk for reading failure. Across 38 child care sites, 220 children were identified as "at risk" for reading failure due to their performance on a screening measure of early literacy skills and randomly assigned to receive immediate or delayed intervention. The intervention consisted of eighteen 30-minute lessons delivered twice weekly for 9 weeks and focused on teaching critical emergent literacy skills within small groups. Hierarchical linear models were used to nest children within center and measure treatment and dosage effects for students' residualized gains in rhyming, alliteration, picture naming, and print and letter knowledge skills. Results indicated significant treatment effects on two of four outcome variables (rhyming and alliteration) and significant dosage effects on all four variables. The study demonstrated a significant positive impact of this intervention for prekindergartners at risk for reading failure.

Errors in Multi-Digit Arithmetic and Behavioral Inattention in Children With Math Difficulties

Raghubar, K., Cirino, P., Barnes, M., Ewing-Cobbs, L., Fletcher, J., Fuchs, L. — Fri, 12 Jun 2009 13:16:35 PDT

Errors in written multi-digit computation were investigated in children with math difficulties. Third- and fourth-grade children (n = 291) with coexisting math and reading difficulties, math difficulties, reading difficulties, or no learning difficulties were compared. A second analysis compared those with severe math learning difficulties, low average achievement in math, and no learning difficulties. Math fact errors were related to the severity of the math difficulties, not to reading status. Contrary to predictions, children with poorer reading, regardless of math achievement, committed more visually based errors. Operation switch errors were not systematically related to group membership. Teacher ratings of behavioral inattention were related to accuracy, math fact errors, and procedural bugs. The findings are discussed with respect to hypotheses about the cognitive origins of arithmetic errors and in relation to current discussions about how to conceptualize math disabilities.

Working Memory in Children With Developmental Disorders

Alloway, T. P., Rajendran, G., Archibald, L. M. D. — Fri, 12 Jun 2009 13:16:35 PDT

The aim of the present study was to directly compare working memory skills across students with different developmental disorders to investigate whether the uniqueness of their diagnosis would impact memory skills. The authors report findings confirming differential memory profiles on the basis of the following developmental disorders: Specific Language Impairment, Developmental Coordination Disorder (DCD), Attention-Deficit/Hyperactivity Disorder, and Asperger syndrome (AS). Specifically, language impairments were associated with selective deficits in verbal short-term and working memory, whereas motor impairments (DCD) were associated with selective deficits in visuospatial short-term and working memory. Children with attention problems were impaired in working memory in both verbal and visuospatial domains, whereas the children with AS had deficits in verbal short-term memory but not in any other memory component. The implications of these findings are discussed in light of support for learning.

Impacts of Comprehensive Reading Instruction on Diverse Outcomes of Low- and High-Achieving Readers

Thu, 23 Apr 2009 14:32:58 PDT

Low-achieving readers in Grade 5 often lack comprehension strategies, domain knowledge, word recognition skills, fluency, and motivation to read. Students with such multiple reading needs seem likely to benefit from instruction that supports each of these reading processes. The authors tested this expectation experimentally by comparing the effects of Concept-Oriented Reading Instruction (CORI) with traditional instruction (TI) on several outcomes in a 12-week intervention for low achievers and high achievers. Low achievers in the CORI group were afforded explicit instruction, leveled texts, and motivation support. Compared with TI students, CORI students scored higher on posttest measures of word recognition speed, reading comprehension on the Gates-MacGinitie Reading Test, and ecological knowledge. CORI was equally effective for lower achievers and higher achievers. Explicitly supporting multiple aspects of reading simultaneously appeared to benefit diverse learners on a range of reading outcomes.

Retrieval of Simple Addition Facts: Complexities Involved in Addressing a Commonly Identified Mathematical Learning Difficulty

Hopkins, S., Egeberg, H. — Thu, 23 Apr 2009 14:32:58 PDT

There exists a substantial number of studies that have identified a subset of low-achieving mathematics students who do not develop a reliance on retrieval for simple addition but who continue to use a counting strategy to solve these problems. There are few studies, however, that have focused on how retrieval of simple addition facts may be improved. This study employed a combined methodological approach to examine the effect extended practice had on increasing a reliance on retrieval for simple addition. An intervention aimed at improving the efficiency of extended practice was also piloted. Although most students improved with extended practice, the extent of improvement was not practical for all students and the intervention did not generally improve the effectiveness of extended practice. The findings emphasize the critical importance of continuing such research and draw attention to the complexities involved in addressing retrieval difficulties for simple addition.

Objective Criteria for Classification of Postsecondary Students as Learning Disabled: Effects on Prevalence Rates and Group Characteristics

Sparks, R. L., Lovett, B. J. — Thu, 23 Apr 2009 14:32:58 PDT

This study examined the consequences of classifying postsecondary students as learning disabled (LD) using five objective sets of criteria: IQ-achievement discrepancies (1.0 to 1.49 SD, 1.5 to 1.99 SD, and ≥ 2.0 SD), DSM-IV criteria, and chronic educational impairment beginning in childhood. The participants were 378 postsecondary students from two universities who had been previously classified as LD and were receiving instructional and/or testing accommodations. The agreement between diagnostic models was often low, both in terms of the proportion of students identified as well as which students were identified by the models. The discrepancy models identified the largest proportions of students as LD (10% to 42%), whereas fewer than 10% of participants met either of the other sets of criteria, and 55% of the participants were not classified as LD by any of the models. Implications for further research and practices in postsecondary settings are discussed.

The Role of Multidimensional Attentional Abilities in Academic Skills of Children With ADHD

Preston, A. S., Heaton, S. C., McCann, S. J., Watson, W. D., Selke, G. — Thu, 23 Apr 2009 14:32:58 PDT

Despite reports of academic difficulties in children with attention-deficit/hyperactivity disorder (ADHD), little is known about the relationship between performance on tests of academic achievement and measures of attention. The current study assessed intellectual ability, parent-reported inattention, academic achievement, and attention in 45 children (ages 7—15) diagnosed with ADHD. Hierarchical regressions were performed with selective, sustained, and attentional control/switching domains of the Test of Everyday Attention for Children as predictor variables and with performance on the Wechsler Individual Achievement Test—Second Edition as dependent variables. It was hypothesized that sustained attention and attentional control/switching would predict performance on achievement tests. Results demonstrate that attentional control/ switching accounted for a significant amount of variance in all academic areas (reading, math, and spelling), even after accounting for verbal IQ and parent-reported inattention. Sustained attention predicted variance only in math, whereas selective attention did not account for variance in any achievement domain. Therefore, attentional control/switching, which involves components of executive functions, plays an important role in academic performance.

Confirming the Factor Structure of Attention-Deficit/Hyperactivity Disorder Symptoms in College Students Using Student and Parent Data

Proctor, B. E., Prevatt, F. — Thu, 23 Apr 2009 14:32:58 PDT

This study used confirmatory factor analysis to compare one-, two-, and three-factor models of attention-deficit/hyperactivity disorder (ADHD) symptoms to determine which model is the best fit for the data. Participants were 190 clinic-referred college students who had been evaluated for ADHD, 155 of whom had received a diagnosis. Data consisted of both self- and other (e.g., parent) ratings of both current and childhood symptoms. Symptoms came directly from the DSM-IV criteria for ADHD. A three-factor model, consistent with the DSM-III, was superior for current and childhood symptoms, regardless of rater (i.e., self or parent). The primary implication for these findings is that there may be a viable Impulsive subtype of ADHD within the adult population. Further research might include a closer examination of the unique functional limitations associated with impulsivity, as well as the development of diagnostic items that maximize model fit.

Working Memory, Short-Term Memory, and Reading Disabilities: A Selective Meta-Analysis of the Literature

Swanson, H. L., Xinhua Zheng, , Jerman, O. — Thu, 23 Apr 2009 14:32:58 PDT

The purpose of the present study was to synthesize research that compares children with and without reading disabilities (RD) on measures of short-term memory (STM) and working memory (WM). Across a broad age, reading, and IQ range, 578 effect sizes (ESs) were computed, yielding a mean ES across studies of —.89 (SD = 1.03). A total of 257 ESs were in the moderate range for STM measures (M = —.61, 95% confidence range of —.65 to —.58), and 320 ESs were in the moderate range for WM measures (M = —.67, 95% confidence range of —.68 to —.64). The results indicated that children with RD were distinctively disadvantaged compared with average readers on (a) STM measures requiring the recall of phonemes and digit sequences and (b) WM measures requiring the simultaneous processing and storage of digits within sentence sequences and final words from unrelated sentences. No significant moderating effects emerged for age, IQ, or reading level on memory ESs. The findings indicated that domain-specific STM and WM differences between ability groups persisted across age, suggesting that a verbal deficit model that fails to efficiently draw resources from both a phonological and executive system underlies RD.