Who are the Learning Disabled?

Is There a Future for A Cognitive Basis?

Evidence from Meta-Analyses and Longitudinal Research

H. Lee Swanson University of California-Riverside Institute for Education Sciences June , 2009

Overview of Meta-Analyses

1. Meta-analyses of Cognitive and RTI Research (in process) —with Brenda Arellano, Loan Tran and Tori Sanchez 2. Meta-Analysis of Adults with RD  Funded by NIFL (with Ching-Ju (Rosie) Hsieh —under review 3. Meta-Analysis of Memory and RD (JLD,2009 with Xinhua Zheng and Olga Jerman)

Overview of Reading and Math Projects

4. Meta-Analysis of Correlational Data on Phonological Awareness, Rapid naming and Reading (

Review of Educational Research

, 2003) Key Collaborators Guy Trainin, Denise Necoechea 5. Meta-analysis of Discrepancy and Non Discrepancy Poor Readers (

School Psychology Review

-2000) Key Collaborator —Maureen Hoskyn

Overview of Reading and Math Projects

  6. Current —Math Disabilities vs. RD, RD and MD —2007

Review of Educational Research

Key collaborators —Olga Jerman, Georgia Dukas, Rebecca Gregg    7. Meta-Analysis of Experimental Intervention Research in LD (RER, 1998, JLD, 2000, 2003) Several collaborators — Key collaborators- Maureen Hoskyn and Carole Lee

Issue 1. Progress Toward Operational Definitions

 Agree on Subtypes relevant to academic outcomes----Three currently  New —directions explore high order definitions —problem solving, comprehension  Explore Cognitive Basis for definitions

Assumption related to the definition

 1. Not due to inadequate opportunity to learn, general intelligence, or to significant physical or emotional disorders, but to basic disorders in specific psychological processes (e.g., remembering the association between sounds and letters).

 2. Not due to poor instruction, but to specific psychological processing problems that have a neurological, constitutional, and/or biological base.

 3. Not manifested in all aspects of learning. Such individual’s psychological processing deficits depress only a limited aspect of academic behavior. For example, such individuals may suffer problems in word recognition, but not calculation.

How researchers generally operationalize SLD

   1. There are two subtypes that have some consensus: reading disabilities and mathematical disabilities. –also consider comorbid group 2. These subtypes are defined by standardized (normed referenced) and reliable measures of intelligence and achievement. The most commonly used intelligence tests are from the Wechsler measures and common achievement tests that include measures of word recognition or arithmetic calculation (e.g., WIAT, WRAT, WRMT).

 3. In general, individuals with IQ scores (e.g., verbal) equal to or above a standard score of 85 and reading subtest scores equal to or below the 25th percentile and/or arithmetic subtest scores equal to or below the 25th percentile reflect two high incidence disorders within LD: reading (word recognition), and arithmetic (computation, written work).

 4. By far, the subtype that has received the most research attention is reading disabilities.

 Some issues in the area of cognition  1. Clouded by conflicting evidence on IQ and reading discrepancy research —  (logic that similarities in overt behavior reflect the same inefficiencies and/or of cognitive processes —consider MD and RD)  2. Clouded by previous cognitive intervention research (poor generalization to changes in academics)  3. Psychometric aspects of measures in question

 4. Inadequate research framework which clouds interpretation of outcomes  5. Knowing cognitive deficits does not indicate teaching directions  6. There are few analogs (low inference observation measures) linking cognitive performance to classroom performance

Perspective

 1. Purpose of assessing cognition is to explain the “why” and “predict” how individual differences account for treatment outcomes  2. Purpose of an instructional approach (e.g., RTI) is to monitor the intensity of intervention (instruction) and make systematic changes as a function of overt performance —  Pt----the approaches are complementary  Pt-The study of cognition has the potential to outline constraints in learning when individual differences cannot be explained as a function of best instructional practice  Pt —instruction accounts for less than 20% of the variance in effect sizes (Swanson, 1999;

1. Methods 2. Age 1. Sequencing 2. Explicit practice Table 2. Regression model predicting effect size as a function of methods composite score, age, and instructional components Χ 2 beta Standard error 20.78*** 1.11

-0.03

-0.01

0.01

0.01

0.2

7.39** 0.03

0.18

0.09

0.08

3. Novelty 4. Attributions 5. Reinforcement 6. Peer modeling 7. Task reduction 8. Advanced organ 9. Questioning 10. One-to-one instruction 11. Control difficulty 12. Technology 13. Elaboration 14. Skill modeling 15. Small group instruction 16. Supplemental cues 17. Strategy cues 18. Large group learning 1.07

0.04

0.25

0.26

2.66

8.23*** 2.94

0.45

0.18

0.95

0.52

3.89* 4.48* 0.91

4.63* 4.17* -0.06

-0.06

-0.06

-0.08

-0.09

0.19

-0.13

-0.04

0.02

0.05

0.09

0.13

0.14

0.12

-0.16

0.12

0.08

0.39

0.16

0.21

0.08

0.09

0.1

0.08

0.08

0.07

0.17

0.09

0.09

0.17

0.1

0.08

R 2 = .20, Χ 2 (df 20, N = 180) = 75.22 Intercept .86 (SE = .16)

                    Table 2

Predictions of Year 3 Problem Solving Accuracy Based on Wave 3 Math Calculation, Problem Solving Knowledge and Wave 1 Fluid Intelligence, Reading and Cognitive Variables

Model 5

Wave 3 Predictors

Problem Solving Knowledge Calculation

Wave 1 Predictors

Fluid Intelligence (Raven) Reading Phon. Know.

Fluency Speed Inhibition Age Sketchpad Phon. Loop Executive B 0.25

0.30

0.13

0.12

-0.01

0.02

-0.004

0.09

-0.15

0.15

0.12

0.19

Model 5

F

(12, 279) = 22.52;

p

< .001,

R2

= .49

SE 0.11

0.08

0.04

0.12

0.10

0.07

0.06

0.06

0.06

0.04

0.06

0.08

ß 0.12

0.27

0.16

0.12

0.10

0.007

-0.004

0.07

-0.16

0.14

0.09

0.15

t

2.13* 3.42** 2.85** 1.00

-0.09

0.33

-0.06

1.60

-2.39* 3.23*** 1.85

2.34*

Math Calculation

Math Calculation

2.5

2.25

2 1.75

1.5

1.25

1 0.75

0.5

0.25

0 -0.25

-0.5

-0.75

-1 -1.25

-1.5

-1.75

-2 -2.25

-2.5

Age 6 Age 7 Age 8

Growth

Age 9 Age 10 At Risk Not At Risk At Risk Not At Risk At Risk Not At Risk

Reading Composite

Reading

2.5

2.25

2 1.75

1.5

1.25

1 0.75

0.5

0.25

0 -0.25

-0.5

-0.75

-1 -1.25

-1.5

-1.75

-2 -2.25

-2.5

Age 6 Age 7 Age 8

Growth

Age 9 Age 10 At Risk Not At Risk At Risk Not At Risk At Risk Not At Risk

Phonological Processing

Phonological Processing

2.5

2.25

2 1.75

1.5

1.25

1 0.75

0.5

0.25

0 -0.25

-0.5

-0.75

-1 -1.25

-1.5

-1.75

-2 -2.25

-2.5

Age 6 Age 7 Age 8

Growth

Age 9 Age 10 At Risk Not At Risk At Risk Not At Risk At Risk Not At Risk

Word Problems

Word Problem Solving

1 0.75

0.5

0.25

0 -0.25

-0.5

-0.75

-1 -1.25

-1.5

-1.75

-2 -2.25

-2.5

2.5

2.25

2 1.75

1.5

1.25

Age 6 Age 7 Age 8

Growth

Age 9 Age 10 At Risk Not At Risk At Risk Not At Risk At Risk Not At Risk

A Focus on the Instructional Side of LD

Issue 2: Determine Meaningful Outcomes

 1. Control group needs to include significant instructional moderators (e.g.,DRP, overlap with treatment)  2. Determine the role definitional moderators

Why Do A Meta-Analysis to address these questions?

 1. Evidence Based —Pattern across several studies vs. single study---vs. overstated or understated information  2. Influence of sample (age, IQ, Discrepancy) and intervention parameters (time,responsiveness vs. resistance to instruction, components of instruction) on outcomes.

 3. Theory Testing---identify the core problem-- area most resistant to intervention  4. Allows for Replication

Interpretation

For the purpose of discussion, Cohen’s (1988) distinctions on the magnitude of the effect size will be used.

* .20 is a small size * .60 is a moderate size * .80 is a large effect size

Table 1 NRP

Moderator Variables Mean Effect Sizes Cohen's Descriptors for

d

&

r

Mean

d

Synthetic Phonics for Various Groups

K & 1st at Risk 1st Normal .64 .54 2nd-6th Normal 2nd-6th Low Achievers Reading Disabled .27 .14ns .36

Unit of Instruction

Tutor Small Group Class .57 .43 .39 MODERATE MODERATE SMALL TRIVIAL SMALL MODERATE SMALL SMALL Mean Effect Correlations Mean

r r

² .30 .26 .13 .07 .18 .27 .21 .19 .09 .07 .02 .00 .03 .07 .04 .04

based intervention and where should we go?

1. Meta-Analysis of Experimental Interventions and LD (e.g., RER, 1989, JLD 2001).

2. Meta-analysis of Dynamic Assessment (e.g., RER, 2001) 3. Meta-analysis of RTI research (in progress)

Criteria

 Computer search, dissertations, state department reports  3000 manuscripts . Control group, average intelligence, minimum of 3 sessions, ES can be calculated.

Final 180 group design (K=1,537) and 85 single subject design studies (K=793)

Bottom line for evidence based studies

 1. Mean ES between LD in control and TRT .56

 2. Mean ES between LD (Exp. TRT) and NLD in .97

 3. Majority of Studies measure Reading  4. Several variables significantly moderate treatment outcomes (IQ & Reading, teacher effects, # components overlap, standardized vs. experimental measures, ratings on internal and external validity)  5. Combined Strategy and Direct instruction most robust procedure

Table 4 Weighted Mean, Effect Sizes for Group Design Studies as a Function of Dependent Measure Category N K LD Treatment vs. LD Control Effect Size Q Effect Size Q Unweighted* Weighted" 95 % Confidence Interval Standard for Weighted Effects Error 1.

Cognitive Processing 1 a. Metacognitive 1b. Attribution I c. Other Processes 2.

Word Recognition 41 9 7 25 54 115 27 17 71 159 2a. Standardized 2b. Experimental 3.

Reading Comprehension 3a. Standardized 3b. Experimental 4.

Spelling 4a. Standardized 4b. Experimental 5.

Memory/Recall 6.

Mathematics 6a. Standardized 6b. Experimental 7.

Writing 7a. Standardized 7b. Experimental 8.

Vocabulary 9 21 28 19 3 16 11 23 35 79 80 58 176 16 38 44 138 24 .8

18 54 20 34 71 22 49 67 7 60 20 .87 .98

.79

.65

.71 .79

.72

.82 .45

.84

.54 .61

.48

.81 .58 .41

.59

.84 .37

.80

.79 .54

.80

.62

.46

.57

.62

.53

.72

.45

.81

.44

.45

.44

.56

.40

.33

.42

.63

.36

.68

.78

Lower Upper .48 .61

.66 .94

.44 .79

.38 .53

.52 .62

.54 .69

.48 .60

.68 .77

.36 .54

.75 .86

.37 .52

.34 .57

.33 .54

.43 .70

.33 .46

.23 .46

.34.51

.54 .72

.14 .58

.59. 78 .66 .89

.03

.07

.08

.03

.02

.04

.03

.02

.05

.02

.04

.06

.05

.06

.04

.05

.04

.05

.

II

.04

.05

Table 4 continued 9. Attitude/Self-Concept 10. Intelligence II. General Reading 12. Phonics/orthographic 12a. Standardized phonics 12b. Experimental phonics 13. Global Achievement (Grades, total achievement) 14. Creativity 15. Social Skills 16. Perceptual Processes 17. Language 3 13 10 9 25 9 15 29 8 21 10 N 86 32 31 175 60 78 21 K LD Treatment vs. LD Control Effect Size Q Effect Size g Unweighted* Weighted .68 (.69) .58 (.59) .60 (.50) .70 (.36) .72 .76 .91 (.76) .39 .41 .52 .64 .67 .60 .45 95 % Confidence Interval Standard for Weighted Effects Error Lower Upper .33 .30 .41 .60 .62 .52 .31 .45 .52 .65 .69 .73 .67 .58 .03 .06 .06 .02 .03 .04 .07 11 .84 (.49) 36 .46 (.22) 37 52 .74 (.65) .54 (.48) .70 .52 .41 .30 .26 .17 .36 .28 .87 .51 .35 .44 .09 .05 .04 .04

TABLE 25. Mean Effect Sizes on Instructional Components Comparing LD in Treatment Conditions to NLD Participants Components 1. Sequencing 2. Drill-repetition-practice-feedback 3. Orienting to process or task 4. Question/answer verbal interaction 5. Individual plus small group 6. Novelty 7. Strategy attributions (self-monitoring) 8. Systematic probing

N

13 9 8 3 16 14 10 6 Mean 0.96

0.78* 1.13

1.2

0.95

0.94

0.80

0.73*

SD

0.55

0.44

0.52

0.46

0.53

0.54

0.53

0.38

9. Peer mediation (tutoring) 10. Segmentation 11. Advanced organizers 12. Directed questioning 13. One-to-one tutoring 14. Control for task difficulty 15. Technology 1 10 8 2 12 5 6 0.52* 1.04

1.31

1.06

0.85

1.21

0.97

0.62

0.52

0.55

0.54

0.43

0.74

16. Elaboration 17. Teacher modeling 18. Small group interaction 1 9 12 1.5

0.93

1.01

19. Parents as mediators 20. Strategy cuing 1 5 1.68

0.74*

Note.

NLD served as a control group and did not participate in treatment.

N,

number of studies ,*effect sizes at .80 and below 0.57

0.56

0.72

Issue 3: Determine the moderating role of IQ

What about Bob (IQ) ?

 1. Does IQ relate to treatment outcomes ?

 Rephrase the question —if IQ is left out of the definition will it influence treatment outcomes?

Instructional Outcomes as A Function of IQ and Reading Level

Bottom Line ON IQ

 1.

LD in Exp. Condition vs. average

ES=.69 for IQ+RD information  ES=1.41 for no IQ + RD information  2.

LD in Exp. vs. LD in Control

 ES=.63 for IQ+RD information  ES=.82 for no IQ +RD information  ES=.60 for IQ+RD+Math information

Mixed Regression Modeling for Predicting Estimates of Effect Size in Cognitive Processing

Model 1 Model 2 Model 3 Model 4 Model 5 Predictor Variable

Age Word recognition Verbal IQ Discrepancy contrast RD-IQ contrast LA-IQ contrast Spelling -6.95*** -1.14 3.29** -.43

-4.79*** .04

6.32** .15

-4.98*** -.07

2.96** .96 -2.14* -.01

2.81** .27

Model 6

-5.42*** .74

2.96** 1.12

-1.66

.52 .32 -.61

.49

.70 .47 phonol. Processing Pseudo-word reading Real-word phonetic analysis Automaticity Memory Lexical knowledge Syntactical knowledge Spatial ability Motor ability REML Log Likelihood -3.08** -.65 -4.22*** 511.95

.28 3.09** 3.61** 3.21*** .76

520.56

-.72

.56

-.43

-.13

1.57

2.53** .93

.00

538.14

527.20

-.43 .90 -.40 .16 1.85

2.86** 1.21

.01 533.60

-1.00

.21 -1.05 .08

1.35

1.80 1.39

.01

511.46

A speculation

     Based on studies that include optimal instructional conditions —the mean effect size one could expect comparing LD with nonLD is (tier 2 or 3)--- D-R-P (.78) Systematic Probing (.73) Peer Mediation (.52) Strategy Cuing (.74)  Mean ES=.69 under evidence based instruction---which may varying depending on the entry of new data--

Issue 4:Develop Standardized Measures related to Dynamic Assessment

 Can we detect LD early with DA procedures?---longitudinal research  DA of Cognitive and/or Academic?

Synthesis of Experimental on Dynamic Assessment (RER, 2001)

 Criteria for Selection  1. Published Refereed Journal  2. Control group comparison (between and within comparisons) for DA vs. static or traditional measurement (no feedback)  3. 30 articles from 303 potential (majority eliminated because ES could not be calculated, duplicate data) articles analyzed

Questions

 Is new information gained by DA procedures relative to traditional assessment?

 Are some groups of children more responsive then others?

 Which DA procedures yield the highest outcomes (relative to traditional assessment )?

Item

Age Range

1. Younger « 10) 2. Middle (10-13) 3. Older (> 13)

Domain

1. Verbal 2. Visual Spatial

N

4,480 4,906 2,558 368 11,548

Cla ssifica tion

1. Average Ach.7,523 2. MR 3. LD 4. Uach 5. Hearing 2,645 633 419 350

# Sessions

1. Single 2. Multiple 9,154 2,762

K

Type of Inst.

1. T. Limits 2.Train

8,221 1,695 3. Strat/Monit. 2,000 55 78 31 11 153 98 23 20 8 9 127 37 128 14 22 Effect Size Weighted

95% CI f or

Weighted Effects Lower Upper 0.65

0.36

0.38

0.31

0.48

0.41

0.49

0.1

0.98

0.75

0.48

0.43

0.48

0.21

0.65

0.62

0.31

0.32

0.16

0.45

0.38

0.43

-0.01

0.81

0.58

0.45

0.37

0.45

0.15

0.58

0.7

0.4

0.44

0.47

0.51

0.45

0.55

0.22

1.14

0.91

0.52

0.49

0.52

0.28

0.71

Results and Implications for LD---DA vs. traditional

 1. Lower effect sizes emerge for LD relative to other categories of children  2. Largest ESs occur for underachievers  3. Testing limits (e.g., scaffolding---various cuing procedures) and general strategies (general feedback, modeling strategies) yielded higher outcomes than test-train-test models  Implication---LD sample performance as a function of DA is hard to change relative to other groups--

 IS RTI itself a wait and fail situation???

Issue 5: determine if RTI studies can change risk factor of children already with serious risk factors (beyond what psychometric studies can provide)--- is there better explanatory power knowing general areas of cognition?

Meta-analytic look at RTI findings

Criteria for Selection 1. Published Study (1985-2008) 2. Divided sample into responders and nonresponders 3. Focus on reading-Elementary 4. Reported Pretest Scores by Responders and Nonresponders 5. Reported Standardized scores 6. Allow for calculation of ES Only 9 studies met criteria (119 ES)

Issues facing RTI and how a Meta analysis can help

 1. No (or few) systematic control studies (none meeting the gold standard) comparing RTI with a competing model of classification  2. RTI is a function of instruction (as well as teachers), and because there is no standardized protocol for instruction —how well can people generalize from findings to classify child at risk across school districts?

 3. No consensus on definition of what resistance to instruction should be (slope of 0 or .25 or benchmarks?)---Is the issue really intercept level and not change (slope)?

Group Design RTI Studies (Responder vs. nonresponder in the same evidence-based intervention)

Variable K Mean SD Effect Sizes* ES pretest 62 1.05

0.97

93 1.09

1.27

ES posttest Gains-Total Sample ES gain Score ES corrected Gain Score 51 51 0.41

0.27

0.98

0.65

Weighted Effect Sizes as a Function of Categories Comparing Responders and Nonresponders at Risk for RD

K Weighted Effect Size SE Lower Confidence Post Test Word Identification 18 1.27

0.074

1.12

Upper Confidence 1.42

Homogeneity (Q) 74.97*** Phon./Basic Skills 9 Word Attack 16 Naming Speed Vocabulary IQ 7 8 5 Spelling 10 Behavior Rating 5 Process (DTLA) 6 Orthography 4 1.18

1.53

-0.68

0.81

1.04

0.87

0.3

0.8

0.89

0.11

0.095

0.08

0.16

0.107

0.17

0.23

0.24

0.1

0.96

1.34

-0.86

0.49

0.83

0.53

-0.16

0.33

0.68

1.39

1.71

-0.51

1.14

1.25

1.22

0.76

1.27

1.11

44.43** 155.27*** 12.20

14.13** 11.94

45.68** 39.41*** 4.06

2.86

Weighted Effect Sizes as a Function of Categories Comparing Responders and Nonresponders at Risk for RD

K Weighted Effect Size Standard Error Lower Confidenc e Upper Confidence Pretest Word identification Phon./Skills 16 8 Word Attack 14 0.94

1.19

1.24

0.07

0.11

0.1

0.79

0.96

1.03

1.09

1.41

1.44

Homogeneity (Q) 48.29*** 36.40*** 79.75** Naming Speed IQ Spelling Behavior Ratings 1 -1.07

1 3 1.16

0.86

5 0.024

0.26

0.22

0.34

-0.41

1.38

0.46

0.35

25.73**

Table 4 Effect Sizes for Post-test when Compared to Normed Referenced Measures at Pre-test.

Word Identification Phon. Process/Basic Skills Pre-Test (SS) Responders Mean SD 92.52 14.7

Mean SD 92.55 13.7

Word Attack Mean SD 96.06

8.54

Low responders Effect Sizes Pretest Post-test Spearman Rho 0.71

82.28 9.91

1.02 0.64

1.39 0.77

0.88

81.65 7.29

86.74

9.97

1.47

0.9

1.41 0.84

0 .

8 2 .83

1.13

1.88

0.51

1.35

Tentative Conclusions (RTI Studies)

 1. Pretest differences for some children seriously at risk remain stable —and a source for determining LD  2. Instruction is not robust enough to ignore individual differences in achievement and “perhaps” cognition

Conclusion on Interventions —Who are the SLD ?

1.

2.

3.

Children who yield low outcomes under optimal instructional conditions (components that significantly and positively influence effect sizes Those optimal instructional components that predicted treatment outcomes---Drill-repetition-skills, strategy training and small interactive groups Definition does influence outcomes-IQ and Reading Scores in combination are not irrelevant to instructional outcomes (at least from this data set). Average IQ and low Reading group (< 25 outcomes.

th percentile) appears to be one subgroup most at risk in terms of the magnitude of

The Assessment Side of LD

 What Cognitive Variables are Important in Assessing RD and MD in children?

 Do risk factors related to Cognition go away in adulthood?

Issue 6: What are the important cognitive processes to consider in in children and adults with LD ?

 What are the common cognitive deficits among subgroups?

 What are the non-overlapping cognitive deficits among subgroups?

 What deficient cognitive processes operate independent of classification variables--

Math disabilities: Meta-analysis of published literature

Research and Policy Question

1. Are cognitive deficits comparable between RD and MD children? 2. Does the identification of cognitive processes help in the classification (does it matter) ?

Selection criteria

 1. Pool in excess of 800 articles  2. 85 articles with defined control groups (needed at least a nondisabled control group)  3. Standardized math,reading, and IQ scores  4. 28 studies met full inclusion criteria —

Table 2

Psychological and Demographic Information on Participants

Age IQ Math Reading Chronological Age Matched (N=784) M SD Range 124.51 52.22 72-158 105.59 8.70 80-120 105.64 6.51 96-119 106.80 5.93 96-113 Math Disabled (N=527) M SD Range Effect Size M SD 123.64 58.93 73-157 .12 99.69 8.51 80-119 -.59 84.76 5.93 75-96 -2.19 .34 .40 1.13 98.37 7.68 87-109 -.59 .49

Table 2 Continued

Comorbid (MD & RD)(N=135) M SD Range Math Disabled (N=294) M SD Range Effect Size M SD Age IQ Math 122.49 92.43 84.65 47.49 5.10 2.84 57-322 89-98 81-87 135.76 83.65 56-304 -.54 99.92 86.02 5.64 94-112 .59 7.92 75-88 .26 .99 .16 .24 Reading 82.83 1.25 81-87 100.75 8.28 84-108 1.68 Note. Negative effect size is in favor of contrast group and positive effect size is in favor of MD group.

.47

Table 2 Continued

Age IQ Math Reading Reading Disabled (N=224) M SD Range 131.25 82.30 59-141 96.78 95.75 80.69 7.55 80-107 8.87 85-103 6.75 66-87 Math Disabled (N=250) Effect Size M SD Range M 135.34 76.84 59-142 .08 SD .33 97.83 86.61 8.93 6.56 80-105 -.31 .56 75-87 -1.11 1.50 99.058 8.16 97-1054 2.27 1.16

Table 3 Weighted Effect Sizes, Standard Error, Confidence Intervals and Homogeneity of Categories for Comparisons between MD and non math disabled (MD/NMD), MD and reading disabled (MD/RD), and MD and RD+MD (CMOR) (corrected for outliers).

Comparison MD/NMD MD/RD MD/CMOR 194 58 102 MD/NMD MD/RD MD/CMOR MD/NMD MD/RD MD/CMOR 19 6 10 29 1 15 K Effect Size Standard Error Lower Total Across Categories -.52 .01 -.56 -.10

a .26

a .03 .02 -.16 .22 Upper -.48 -.04 .31 1. Literacy (vocabulary, reading comprehension) -.30 .11 .75 -.58 .10 .13 .05 .07 .06 -.40 -.02 .62 2. Problem Solving-verbal .04 . .05 -.67 . .02 -.40 .25 .88 -.49 . .23 Homogeneity Q 767.05*** 263.35*** 650.86

*** 73.52

*** 2.00 49.30** 242.41

*** . 107.72

Table 3 Continued

Comparison MD/NMD MD/RD MD/CMOR 17 6 10 MD/NMD MD/RD MD/CMOR 23 4 10 MD/NMD MD/RD MD/CMOR 15 0 9 K Effect Size Standard Error 3. Speed-naming Lower -.70 .06 -.83 -.23 -.39 .13 .09 -.49 -.58 4. Visual-spatial Problem Solving -.56 .02 Upper -.19 -.48 .05 -.47 -.31 .04 .51 .09 .06 -.17 .38 5. LTM-retrieval (e.g., general information) .18 .64 -.72 . .44 .09 . .12 -.90 . .20 -.54 . .69 Homogeneity Q 55.70 *** .38 6.01 41.61*** 8.90* 44.03*** 35.49

*** . 10.35

Table 3 Continued

Comparison MD/NMD MD/RD MD/CMOR 16 3 4 MD/NMD MD/RD MD/CMOR 11 4 9 MD/NMD MD/RD MD/CMOR 43 19 20 K Effect Size Standard Error 6. STM-Words Lower -.45 .16 .71 -.26 .03 -.08 .06 -.58 .13 .12 -.10 .46 7.STM-Digits/numbers .07 .14 .11 -.41 -.24 -.30 -.70 -.07 .30 8. WM-Verbal .04 .06 .06 -.79 -.19 .17 .10 .32 .13 Upper -.32 .42 .96 -.61 .04 .42 Homogeneity Q 44.78*** 7.33* 12.61** 48.94

*** 6.35 110.57*** 83.84

*** 139.95*** 86.49**

Table 3 Continued

Comparison MD/NMD MD/RD MD/CMOR 13 13 13 K Effect Size Standard Error 9.WM-Visual Spatial Lower -.63 -.30 .23 .07 .07 .07 -.77 -.44 .08 10. Attention .38 Upper -.48 -.16 Homogeneity Q 28.14** 35.43** 14.10 MD/NMD 8 -.15 .09 -.33 .03 34.83

*** MD/RD 0 - - - - - MD/CMOR 2 -.57 .11 -.79 -.35 6.97* Note. MD = Math Disabled only, NMD = non math disabled-average achiever, RD = reading disabled, CMOR = comorbid group with both low reading and math; K = number of measures, Lower and Upper = 95% level of confidence range. a Positive effect sizes favor MD and negative effect sizes favor comparison group; *p < 05, **p < .01, ***p < .001.

What About Applied Cognition (Memory) —JLD-2009

 1. Published studies —1970-2008  2. Defined RD and CA matched NONRD sample by Standardized scores  3. Outcomes on at least one STM or WM measure (operationally defined)  4. 88 studies, weighted ES=-.89, STM=-.65, WM=-.67

 5. Low IQ+Low Reading ES (RD vs. NRD)= .49,High IQ+low reading=-.85

 6. 52 % of between study variance explained by Memory

             W Effect Size as a Function of Categorical Variables When Compared to Chronological Age and IQ Matched CCategory Number of Studies M SD K Weighted Effect Size 95% CI for effect size Lower Upper SShort-Term Memory 1. Phonological 2. Pictures 3. Words 4. Digits 5. Letters DDual Task-Trade-off-reorder 7 17 25 11 4 -0.83

-0.90

-0.50

-1.49

-1.06

1.15

1.13

0.66

2.2

0.52

22 53 76 55 13 -0.39

-0.57

-0.55

-0.63

-1.10

-0.50

-0.65

-0.61

-0.69

-1.24

-0.29

-0.49

-0.48

-0.56

-0.95

6. Backwards 7. Preload 16 3 -0.70

-0.53

0.45

0.27

59 7 -0.69

-0.49

-0.74

-0.73

-0.63

-0.26

   NNumber of Studies M  Upper  WWorking Memory-D & C format  9 Counting 10  1Listen/Sentence19  1 Visual- Matrix 26  1 Complex Visual.6

-0.88

-1.51

-0.69

-0.52

 1 Semantic Assoc.10

 1 Digit/Sentence10 -0.81

-1.47

 Story Retelling 4 -0.80

 1Phonol/Rhyming 7 0.32

 D & C=Daneman and Carpenter task format SD 0.55

1.21

0.63

0.17

0.44

2.25

0.7

13 K Weighted Effect Size 95% CI for effect size Lower 32 57 72 20 31 24 9 -0.61

-0.78

-0.84

-0.80

-0.48

-0.37

-0.58

-0.37

-0.74

-0.84

-0.89

-0.86

-0.57

-0.44

-0.68

-0.50

-0.49

-0.73

-0.79

-0.74

-0.39

-0.30

-0.48

-0.24

-0.72

Rapid Naming, Phonological Awareness and Reading

Big Question

 Is Phonological Awareness the most important variable in predicting reading accuracy? or is a more comprehensive cognitive battery called for?

Research Questions

 1.What is the correlational evidence on the relationships between phonological awareness, rapid naming speed, and sight word recognition?

 2. Do other processes play an important role?

 3. Are the correlations between RAN and PA independent —are they sensitive to age?

Selection Criteria

 Dates 1966-2001-Include PA, RAN, and reading (138 studies)  35 Studies Meeting Selection Parameters (report SD, complete intercorrelations)  Correlations (K=2,257)

Table 4 Estimated Intercorrelations Among Cognitive Measures Measures 1 2 3 4 5 6 7 8 9 10 1. Word 3. RAN 2. Phonol.

4. Pseudo word 5. Intelligence 6. Vocabulary 7. Ortho/homo.

8. Spelling 9. Memory 10 Reading comp.

1.0

1.0

.43

.42

.36

1.0

.69

.52

.53

1.0

.42

.28

.36

.63

1.0

.38

.42

.26

.34

.41

.33

.41

.52

.78

.52

.53

.77

.37

.74

.30

.27

.54

.49

.60

.67

.42

1.0

.54

.34

1.0

.70

.58

.45

.68

.39

.44

.64

.38 1.0

.53

.61

.80

1.0

.48

1.0

Note. Phon.=Phonological awareness,Ortho/homo=Orthography/homophones, Reading comp.=Reading comprehension

Conclusions

 1. Predictions of real word reading —  No clear advantages for PA and RAN when compared with other variables  2. Role of Chronological age —age did not appear to play a moderating role in the correlations between RAN and PA

Do process deficits go away with time? Adult Outcomes

 1. Pool in excess of 450 articles- samples > 18 yrs of age and reading scores  2. Articles with RD and defined control groups (needed at least a nondisabled control group)  3. Standardized reading and IQ scores  4. Reported measures independent of classification measures  5. 52 studies met full inclusion criteria —

Table 1

Psychological and Achievement Profiles on Standardized Normed Referenced Measures for Adult Participants with and Without Reading Disabilities

Chronological Age Matched (N=1162) Reading Disabled (N=1719) Effect Size Studies M SD M SD M SD

Norm Referenced

Read. Comp.

General Intell.

33 46 109.87

110.55

11.29

6.89

93.05

104.64

12.29

11.62

1.25

0.26

0.73

0.67

Verbal Intelligence Word Recognition 19 30 110.6

107.19

9 8.24

101.36

88.65

12.63

10.16

0.69

1.64

0.61

0.79

Table 2

Weighted Effect Sizes, Standard Error, Confidence Intervals and Homogeneity of Categories for Comparisons between Adults with and without RD (corrected for outliers).

Comparison Upper RD/NRD RD/NRD RD/NRD RD/NRD RD/NRD K Effect Size Total Across Categories 776 53 0.54

Standard Error 0.01

1. Reading comprehension 1.20

0.04

2. General Intelligence Lower 0.52

1.12

48 20 43 0.20

0.03

2.1 Verbal Intelligence 0.63

0.05

3.0 Reading Recognition 1.37

0.04

0.13

0.5

1.28

0.56

1.28

0.28

0.74

1.44

Table 2

Weighted Effect Sizes, Standard Error, Confidence Intervals and Homogeneity of Categories for Comparisons between Adults with and without RD (corrected for outliers).

Comparison K RD/NRD RD/NRD RD/NRD RD/NRD RD/NRD RD/NRD RD/NRD Effect Size Standard Error Lower 4.0 Speed of Processing (e.g., letter naming, etc) 56 0.96

0.03

5. Phonological Processing 0.88

42 0.77

55 0.87

0.05

6.0 Word Attack 1.33

0.03

7.0 Math 1.25

32 0.75

0.03

8.0 Vocabulary 0.68

29 0.71

0.62

33 11 1.57

0.72

0.04

9.0 Spelling 0.05

10.0 Writing 0.07

1.47

0.58

Upper Homogeneity Q 1.04 184.19*** 0.98 199.08*** 1.41 284.18*** 0.83 189.19*** 0.8 163.52*** 1.67 258.25*** 0.86 162.18***

Table 2

Weighted Effect Sizes, Standard Error, Confidence Intervals and Homogeneity of Categories for Comparisons between Adults with and without RD (corrected for outliers).

Comparison K Upper RD/NRD RD/NRD RD/NRD RD/NRD RD/NRD 34 38 44 6 19 Effect Size Standard Error Lower 11.0 Social and Personal Skills 0.10

0.03

12.0 Problem Solving and Reasoning 0.02

0.11

0.04

13.0 Verbal Memory 0.03

0.53

0.62

0.04

13.1 Visual-Spatial memory -0.39

0.12

13.2 Cognitive monitoring -0.63

0.27

0.06

0.15

0.17

0.2

0.71

-0.14 0.39

Table 2 Weighted Effect Sizes, Standard Error, Confidence Intervals and Homogeneity of Categories for Comparisons between Adults with and without RD (corrected for outliers). Comparison K Effect Size SE Lower Upper 14.0 Perceptual Motor Skills RD/NRD 66 -0.13

0.03

14.1 Auditory Perceptual -0.19

-0.07

RD/NRD 27 -0.18

0.06

14.2 Visual Perceptual -0.31

-0.06

RD/NRD 14 0.13

0.11

-0.09

15. General Information (LTM) 0.35

RD/NRD 9 0.47

0.08

16. External Criterion 0.31

0.64

RD/NRD 11 -0.23

0.05

17.0 Personality -0.33

-0.12

RD/NRD 16 0.28

0.04

0.19

0.37

Note. ; K = number of measures, Lower and Upper = 95% level of confidence range. group NRD = non reading disabled-average achiever, RD = reading disabled; a Positive effect sizes favor NRD and negative effect sizes favor RD

Table 1

Psychological and Achievement Profiles on Standardized Normed Referenced Measures for Adult Participants with and Without Reading Disabilities

K Chronological Age Matched (N=1162) M SD Reading Disabled (N=1719) M SD Effect Size M SD Fluency/RAN 15 105.93

6.36

88.72

16.4

1.01

0.65

Phonol. Processing Word Attack Math Vocabulary 8 105.48

24.03

21 14 17 105.82

106.23

104.89

8.23

8.71

7.39

Spelling 20 107.89

7.02

Writing 8 101.94

7.95

Problem solving/reasoning a 29 11.94

1.88

Memory-Verbal b 21 9.99

3.38

76.26

87.17

93.64

92.3

87.62

88.15

11.32

8.13

16.96

11.88

10.31

11.28

11.07

1.7

2.21

9.88

1.6

1.68

0.88

0.88

1.77

0.81

0.04

0.81

0.68

0.72

0.82

0.649

0.66

1.1

0.3

0.8

RD vs. Slow Learners: More Alike than Different?

Big Question

 Is IQ completely irrelevant in separating various reading groups??

Research Questions

 1. Is the phonological core deficit the only process that holds between the two groups?

 2.Are the effect sizes moderated by Age and/or verbal IQ?

 Problem —what’s low achiever (< 96 on IQ and reading —40 th percentile)  What’s RD (25 th percentile in reading and verbal IQ > 80---designated discrepancy)

Selection of Studies

 1. 20year period —must include comparison of Discrepancy and Non Discrepancy groups  2. Criterion measure was reading recognition  3 Must report Standardized Intelligence and Reading Measures  4. Published in a refereed journal-English  69 potential articles — 19 met criteria-274 effect sizes Mean ES .21 (SD=.65)

Table 1 Age and Psychometric Characteristics of Children with RD and Low Achievers

Variable

Age Word Recognition Verbal Intelligence

RD Group Mean

111.05

79.82

99.46

RD Group SD

33.34

5.75

4.79

LA Group Mean

110.92

84.09

83.64

LA Group SD

33.48

5.72

4.91

Magnitude of Effect Size by Category of Dependent Measure.

Category of dependent measure K Mean Hedge’s g SD Range

Phonological processing:

Phonological processing 34 .27

.50

-.67 to 1.36

Q

117.19** Pseudo-word reading Real-word phonetic analysis Automaticity Spelling

Memory

Syntactical knowledge Lexical knowledge

Visual Spatial Reasoning:

Visual-motor skills Spatial processing 18 26 55 8 59 11 17 9 37 .29

-.02

.05

.19

.12

.87

.55

.15

.36

.39

.52

.45

.43

.89

.24

.63

.80

.67

-.50 to 1.01

-1.44 to 1.05

-1.21 to .85

-.34 to .93

-3.56 to 1.24

.55 to 1.29

-.50 to 1.85

-1.36 to 1.29

-1.36 to 1.85

25.98* 61.09** 93.11** 14.32* 159.07** 5.47

47.74** 54.57** 150.45**

Conclusions

 Verbal IQ and Age moderate the overall level of cognitive performance.

— This conclusion is different than saying IQ is irrelevant

Overall Conclusions

 Who are the SLD?

 Children with average IQ’s (>84) with reading and/or math scores below the 25 th percentile whose academic performance outcomes remain below an ES of .70 (when compared to normal achieving peers) after intense exposure to optimal instructional conditions

 1. There evidence to suggest that IQ (at least verbal IQ) should “not” be thrown out of the definition.

 2. Two processes are critical (PA, WM) when determining the subtypes of disabilities.

 3. Children at great risk for SLD are those exposed to optimal instructional conditions who are in the average range of intelligence and also experience processing inefficiencies in PA and WM.

Where to go from here?

Swanson, H.L. (2008) Neuroscience and Response to Instruction (RTI): A complementary Role In C. Reynolds & E. Fletcher-Janzen (Eds.) Neuropsychological Perspectives on Learning Disabilities in the Era of RTI: Recommendation for Diagnosis and Intervention.

NY: John Wiley & Sons.

Steps 1-3 Step 1a Select children who have average intelligence, score below the 25 th percentile in reading or math and been provided intense instruction but show limited growth in achievement Step 1b Select a parsimonious domain embedded within a model of learning (e.g., Reading, Mathematics). Step2 Select tasks that both represent the domain (e.g., working memory) and are sensitive to individual differences in learning (construct validity).

Step 3 Determine the locus of ability group differences on those tasks.

Step 4

Step 4: Delineate the cognitive processes that underlies ability group performance.

a. Relate process measures with ability differences in academic functioning b. Determine if process measures account for the major variance in academic performance c. Determine which process measures best predict academic performance.

d. Eliminate process measures that poorly correlate with academic performance.

e. Demonstrate interaction between ability group and process manipulation f. Partial out the effects of academic ability.

g. Determine neurological correlates between children with and without LD.

Step 5

Step 5: Categorize processing difficulties.

a. Parameter differences b. Sequence differences c. Route differences d. Strategy differences

Step 6

Step 6 :Teach LD children to process as NLD children, thereby attempting to raise their performance to a level similar to their counterparts.

a. If instruction fails to induce change, move to Step 7.

b. If instruction induces change, determine if both ability groups used the same processes c. Collect concurrent measures on classroom functioning

Step 7

 Step 7: Formulate a metatheory of learning disabilities by designating the parameters susceptible and not susceptible to instruction  a.If anomalous data occur, return to Step 1.b.  b. If additional data confirm theory, broaden context (e.g., determine influence of non cognitive classroom variables on learning).