Barbara W. Wise & Lynn Snyder, University of Colorado
Learning Disabilities Summit: Building a Foundation for the Future White Papers
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Expert educators continuously evaluate their students' performance, adapting instructional programs to be as effective as possible for each child. This paper considers the information educators need to make these adaptations. The term educator refers here to professionals along the whole cascade of teaching services, from general classroom teachers, to learning specialists in smaller reading or special education settings, to therapists and specialists working one on one with the student experiencing difficulty. Because of reading's critical role in learning and because of the prevalence of reading problems in children referred for special education, the paper focuses on decisions educators make about children with specific reading disabilities (SRDs), with specifically poor comprehension, or both. We consider these separately, because different kinds of language deficits underlie the two kinds of reading problems.
Research from the last twenty years clearly suggests how to screen, identify, teach, and evaluate children with language-based reading difficulties. We refer to some of this research in this paper. However, the chapter mainly considers the clinical judgments that expert educators add to this knowledge to recognize children with learning disabilities and to construct and evaluate their educational programs. We explore some training and classroom management ideas to help teachers work towards this goal without exhaustion. The chapter closes by recommending that educators and researchers collaborate to evaluate and improve treatments and scale up the best treatments, so that more and more children will receive effective methods and practices for their needs.
Given the potential social stigma (Sapon-Shevin, 1987; Smith & Nagle, 1995) and sometimes reduced teacher expectations (Tauber, 1998) that can be caused by labeling a child as having a learning disability, why do we still advocate using the label? Clearly, labels can be justified only if they are reliable, valid, and useful (Pennington, 1991). A label is reliable if it identifies a learning difference that remains stable across many tests and settings. A label of a learning disability is valid if it identifies a learning difference related to processes intrinsic to the learner. It is valid and instructionally useful if children with that label benefit from treatments theoretically compatible with the identified underlying processes more than from other treatments. Demonstrated advantages for such treatments are indeed what justify and require the continued identification of children with valid, instructionally useful labels. Many labels (e.g., visual or auditory closure difficulties) that were applied in the early 1970s and the treatments that accompanied those labels did not prove either valid or helpful, and they have thankfully fallen out of use (Hammill, 1972; Vaughn, Gersten, & Chard, 2000).
In this paper we focus on variability within two major learning disability labels, both involving reading difficulties, because reading is so crucial for success in schools and because reading disabilities are so prevalent in special education settings (Langenberg, 2000). Much well-controlled research covered in this report identifies core deficits underlying many cases of reading disabilities and indicates reliable tests that can discriminate children with and without the deficits. Research has also identified aspects of theoretically valid programs that help such children more than other programs do. All this research yields practical recommendations about screening, teaching, and evaluating the progress of these children.
We focus first on SRD, often called dyslexia (Lyon, 1995), the most prevalent learning disability. It is usually based on underlying core deficits in phonological (or speech-sound based) processing. Problems in phoneme awareness (the ability to identify and manipulate sounds inside syllables) and phonological decoding (the sounding out of words) are abilities that suffer when phonological processing is weak, and these weaknesses lead directly to problems in word reading. Children with weak phonological processes also struggle secondarily with reading comprehension, for two reasons. First, comprehension suffers when they misread words. Second, comprehension can still fail if remedied word reading remains so slow and effortful that it uses too much attention (Perfetti, 1985). Children whose reading comprehension is hindered solely by phoneme awareness and decoding comprehend well when listening to stories, but have problems when reading the stories themselves.
On the other hand, a less common group of children with specifically poor comprehension struggle with formulating main ideas, summaries, and inferences both when they listen to stories and when they read them themselves. The difficulties appear despite these children's normal phoneme awareness and decoding skills. These comprehension problems seem usually to relate to underlying core deficits in higher-level language skills, such as difficulties with non-literal meaning, vocabulary, and syntax.
Of course, real children with language-based reading problems present with unique profiles with different combinations of deficits and strengths that should affect the design of their optimal instructional program. Their abilities vary in phonological processes (phonemic awareness, memory, and naming speed, discussed later), with or without problems in higher language skills. Their profiles and their programs should also vary depending on strengths and weaknesses in other reading-related abilities such as orthographic memory, attention, and motivation. Verbal IQ, vocabulary, educational background, emotional and behavioral factors, and the home literacy environment also affect each child's profile.
Are there other ways to have difficulty with reading that are not based on language-based learning disabilities? Certainly there are! Other causes of reading difficulties include attention problems, inconsistent education, and problems due to learning to read in a second language. Other children struggle with reading due to mental retardation, sensory deficits, or emotional problems. These children's classroom behaviors, screening, diagnosis, and treatment differ from those of the children with learning disabilities who are the focus of this paper. Their reading should be instructed concurrently with or following the treatment of their primary deficit.
The last three decades of research have yielded a positive history and an optimistic future for the identification and treatment of SRDs. Research in the 1970s moved away from definitions and treatments based on underlying perceptual deficits, such as "visual or auditory closure or figure-ground difficulties" (Hammill, 1972; Vaughn et al., 2000; Vellutino, 1979). Later research moved the field beyond the "exclusionary" definition of Public Law 94-142, which said all that reading disabilities were not but not what they were (Lyon, 1995). The current working definition of SRD results from the work of seven professional organizations, including the National Institute of Child Health and Human Development (NICHD). It identifies a core deficit in phonological or analytic language processes, involving awareness and efficiency in using speech-based codes, underlying most cases of SRD (Lyon, 1995). According to this research-based, working definition:
Dyslexia is one of several distinct learning disabilities. It is a specific language-based disorder of constitutional origin characterized by difficulty in single word decoding, usually reflecting insufficient phonological processing. The difficulties in single word decoding are often unexpected in relation to age and other cognitive abilities; they are not the result of generalized developmental disability or sensory impairment. Dyslexia is manifested by variable difficulty with different forms of language, often including, in addition to problems in reading, a conspicuous problem with acquiring proficiency in writing and spelling.
Twin and family studies in behavioral genetics (e.g., Gayan et al., 1995; Olson, Forsberg, Gayan, & DeFries, 1999; Scarborough, 1990) and research in the function and structure of the brain (Frith, 1997; Hynd & Hiemenz, 1997; Shaywitz, 1996; Zeffiro & Eden, 2000) both suggest a constitutional origin for SRDs. Reading-level match studies support a causal role for phonological deficits, since older children with SRD perform worse in phoneme awareness and phonological decoding than do younger normal readers who read real words at equivalent levels (Olson, Wise, Conners, Rack, & Fulker, 1989; Rack, Snowling, & Olson, 1992). Furthermore, phoneme awareness in kindergarten is one of the strongest predictors (along with letter knowledge) of reading through elementary school (Adams, 1990). Finally, intervention studies validate training in phoneme awareness and decoding. This training, when integrated and applied to reading accurately in context, leads to gains beyond phonological skills into reading itself (Hatcher, Hulme, & Ellis, 1994; Lovett et al., 1994; Torgesen, Wagner, & Rashotte, 1997; Wise, Ring, & Olson, 2000).
It is important to note that the phonological deficits underlying SRDs, and indeed the category itself, are a matter of degree, as with all cognitive processes. No absolute level of phoneme awareness clearly defines how many children have SRDs. The percentage of children that will be identified depends entirely on the criteria set. Research estimates in the 1980s tended to include the lowest 10% of readers with average or above-average IQ. More recently, Lyon cited findings by the Shaywitz's and other researchers to suggest that as many as 20% of children have phonological skills weak enough that reading is one of the most difficult tasks they will have to master in school (Lyon, 1999). The criteria chosen for identification will depend on how many children society decides it can afford to provide with the intensive, individualized instruction required by the appropriate special education that has been so eloquently described by Zigmond (1997).
We propose that the more educators know, the stronger their programs become, and that the better supported they are by technology and personnel, the more children can be identified early and helped efficiently. Lyon (1999) describes strong advantages for early intervention: 90-95% success for students who begin remediation before third grade versus 25% success for children who do not begin until nine years of age. Thus, the earlier children are recognized for risk, the more children can be helped, whether with appropriate instruction in the classroom, with supplemental intensive small group instruction, or with remedial special education services.
Research suggests that interventions for children at risk for SRD should at least improve their deficient phoneme awareness, decoding, and fluency (Kame'enui, Simmons, & Coyne, 2000). We now report research on the remediation of these deficits as well as problems in comprehension that result for children with reading disabilities.
Improving deficient phoneme awareness and decoding. Research has not identified a "best" method to improve phoneme awareness (Wise, Ring, & Olson, 1999; Wise, Ring, Sessions, & Olson, 1997) or decoding or fluency (Hall & Moats, 1999). However, these studies do suggest components that should be included in programs for children with phonological deficits. These children need first to recognize and manipulate sounds easily within words (phoneme awareness), in order then to learn and use the "alphabetic principle" at the base of the English sound-to-print system (Liberman & Shankweiler, 1985). If a child cannot easily analyze the difference in the order of sounds in, for example "fist" vs. "fits," the child must memorize each word as a whole unit. After children have improved in phoneme awareness, they can learn to decode the English print-to-sound system and master decoding and word reading.
Aiming for transfer of phonological training. The studies cited above and the experiences of educators suggest that well-structured phonological training should help children make substantial gains in phonological decoding and accurate word reading. The fact is that many researchers and educators are indeed succeeding in helping more and more poor and non-readers become accurate readers. Justified satisfaction from this progress should not, however, lead us to be smug. Yes, many studies have found impressive differential effects in phonological and word level skills from interventions with explicit vs. less explicit phonological training (Hatcher et al., 1994; Lovett et al., 1994; Torgesen et al., 1997; Wise, Ring, & Olsen, 2000). However, these studies had difficulty showing similar differential gains in reading rate and in comprehension. These researchers also reported a discouraging lack of transfer of differential gains one and two years after treatment ended, relative to the less explicit treatments. Other researchers suggest that children need to apply the skills in well-structured programs, balancing foundation-level skills with work in automaticity and application in accurate reading for meaning in context (Brady & Moats, 1997; Snow, Burns, & Griffin, 1998).
Educators who work one on one, who are able to individualize their instruction, and who can keep students as long as they need to ensure independent use of self-correction and comprehension strategies have some students who maintain gains after treatment (Uhry, 1997; Wise, 2001). However, designing studies of long-term transfer can raise ethical concerns, if researchers must withhold the most effective treatment for a comparison control condition long enough to show follow-up differences two or five years later. If progress from treatments differs significantly after one year at post-test, is it ethical to withhold the better treatment from a control group? On the other hand, the research community needs long-term follow-up to be sure that treatments differ. The research and clinical communities need to grapple with this dilemma to find creative solutions and to consider how to interpret current studies that have not attempted long-term follow-up (Viall, 2001).
Improving fluency and automaticity. The research reported in the last section converges with other research findings to suggest that mastering phoneme awareness and decoding are necessary, but not sufficient, components of early reading instruction (Wise, 1999). If a child labors at decoding words accurately, s/he will not do so when reading for pleasure. Indeed, until foundation-level skills become automatic, most children with reading disabilities will experience more work than pleasure in reading.
In pilot studies, Wise, Olson, and Ring (2000) were surprised how suddenly and completely engaged children with reading disabilities became with very simple programs that speeded practice with words the children had previously mastered for accuracy. Many researchers are using computer programs to practice repeated speeded readings of high frequency words and sub-word units to improve automaticity (Blok, Oostdam, Otter, & Overmaat, in press; Lewin, 1997; Van Daal & Van der Leij, 1994; Wolf, Miller, & Donnely, 2000). Computer programs seem to be ideal to help reading become automatic. Future research may suggest which children will profit most from this kind of instruction.
Improving comprehension for students with specific reading disabilities. Vaughn and colleagues have studied comprehension instruction in small groups of students with learning disabilities, with large effect sizes (Vaughn et al., 2000). Vaughn and her colleagues (2000) and Williams (1993) emphasize extensive practice at appropriate instructional reading levels for children with decoding difficulties. Except for adjusting reading levels for decoding difficulties, their research is relevant for children with comprehension problems without word recognition problems. Therefore, we report the studies later, in the section on specific comprehension difficulties.
Effects of naming speed deficits. While the above research suggests ways to improve word recognition, automaticity, and comprehension for most children with learning disabilities, some children retain a slow reading rate. Certainly it is good that such children read better than they did before remediation, but their continued slow reading reduces their enjoyment of reading and probably hampers comprehension. These children may be those that are most resistant to treatment, with "double deficits" in phoneme awareness and in "naming speed" (Felton, 2001; Wolf, 1999). They currently challenge researchers and teachers.
Naming speed tasks typically require children to name as many pictured objects, colors, or letters as quickly as they can. Poor naming speed can exist alone or coexistent with poor phoneme awareness or with the higher-level language problems of specifically poor comprehenders reported in the next section. Wolf believes that children with good phoneme awareness but slow naming speeds are not only slow readers, but also poor comprehenders (Wolf, Bowers, & Biddle, 2000). Research has not yet clarified exactly what underlies slow naming speed, but it is surely language related. It appears to depend at least on slow speech rates and probably on slow lexical access (Scarborough, 1998b; Wolf, Bowers, & Biddle, 2000).
It is interesting to puzzle through how these underlying language skills predict progress in reading. Phoneme awareness is the strongest predictor of reading progress through elementary school (Wagner, Torgesen, & Rashotte, 1994). Scarborough (1998a) also found that phoneme awareness ability in kindergarten predicted success at the end of second grade in reading. Scarborough also concurs with many other researchers (e.g., Felton & Brown, 1990) who have shown that those who are poor readers in first and second grades tend to remain poor readers into junior high. Predicting forward from second grade testing, Scarborough found that simple literacy scores predicted eighth grade reading better than any other variable. Interestingly, adding phoneme awareness or phonological decoding to the equation at second grade did not improve these predictions. Only when rapid serial naming in second grade was added to second grade literacy did the prediction become more precise about who would struggle with reading and comprehension in eighth grade. This fits Wolf's picture that phonological deficits are more amenable to remediation, while children with "double deficits" in phoneme awareness and naming speed seem more resistant to treatment. On the other hand, phoneme awareness ability in second grade was the best predictor of eighth grade spelling ability.
These kinds of recent findings have turned researchers' attention to naming speed, with a resulting increase in the number of studies on rapid serial naming. Two important questions arise: Can rapid naming be improved, and if so, will its improvement affect reading performance? Suppose naming speed is impossible to change. If that proves to be the case, researchers and educators will look to revising instructional programs to accommodate slow reading and naming speed. In current practice, such revised programs encourage using assistive technology for reading and writing, reducing amounts of printed work, and providing alternative methods of demonstrating learning for children who read and write slowly and with great effort.
On the other hand, it is not yet time to give up on improving the reading rates of children who are slow at serial naming. Most of the research field has been aware of the significant effects of naming speed for less time than it has been aware of the importance of phonological deficits. It is certainly worth seeing what the field can come up with to help these children. Wolf, Denckla, Bowers, and Felton have suspected the importance of naming speed for far longer than most researchers (Wolf, Bowers, & Biddle, 2000). Repeated readings and guided reading have been shown to improve fluency, but rapid naming was usually not measured in these studies (Felton, 2001). Wolf, Miller, et al. (2000) are devising computer programs that they hope will help improve reading rates by working on fluency and on elaborating vocabulary. They believe that the more routes a child has to retrieve a word, the faster his retrieval may be, though this reasonable conjecture has not yet been proven.
The previous discussion suggests that the expert educator will assess, teach, and monitor progress in fundamental skills, build automaticity with speeded practice, and provide extensive opportunities to apply skills in context at instructional levels. S/he does this while teaching and supporting comprehension and while encouraging independent reading and writing away from the classroom to ensure transfer. Accomplishing this in individualized programs is the goal of the expert educator, who begins to sound like a superhero! In a later discussion on modifying instruction to meet individual needs, we examine research and suggest how s/he may accomplish this with neither supernatural powers nor exhaustion. Before considering these ideas in practice, we want to contrast the profiles of children with specifically poor comprehension to those of the children we have been discussing thus far.
Funding for NRCLD is provided by the U.S. Department of Education, Office of Special
Education Programs. Award No. H324U010004. Opinions expressed herein are those of the National
Research Center on Learning Disabilities and do not necessarily represent the position of the U.S.
Department of Education.
© 2007 National Research Center on Learning Disabilities
Last Updated: November 19, 2007
Contact: nrcld@ku.edu