Validity of Alternative Approaches to the Identification of LD: Operationalizing Unexpected Underachievement

1. Validity of Alternative Approaches to the Identification of LD: Operationalizing Unexpected Underachievement Jack M. Fletcher, Ph.D. Carolyn Denton U of Texas- Houston U of Texas- Austin CARS.uth.tmc.edu Jack.Fletcher@uth.tmc.edu Responsiveness-to-Intervention Symposium December 4-5, 2003 • Kansas City, Missouri The National Research Center on Learning Disabilities, a collaborative project of staff at Vanderbilt University and the University of Kansas, sponsored this two-day symposium focusing on responsiveness-to-intervention (RTI) issues. The symposium was made possible by the support of the U.S. Department of Education Office of Special Education Programs. Renee Bradley, Project Officer. Opinions expressed herein are those of the authors and do not necessarily represent the position of the U.S. Department of Education. When citing materials presented during the symposium, please use the following: “Fletcher, J. M., & Denton, C. (2003, December). Validity of alternative approaches to the identification of LD: Operationalizing unexpected underachievement. Paper presented at the National Research Center on Learning Disabilities Responsiveness-to-Intervention Symposium, Kansas City, MO.” Fletcher, J. M., & Denton, C. (2003, December). Validity of alternative approaches to the identification of LD: Operationalizing unexpected underachievement. Paper presented at the National Research Center on Learning Disabilities Responsiveness-to-Intervention Symposium, Kansas City, MO.

2. Learning Disabilities is a Construct • Essential aspect of construct is “unexpected underachievement” • Constructs do not exist independently of how they are measured; all measures are imperfect indicators of constructs (latent variables) • Measurement depends on definition • Definitions and the resultant identification criteria derive from classifications • All classifications are hypotheses that must be tested Fletcher, J. M., & Denton, C. (2003, December). Validity of alternative approaches to the identification of LD: Operationalizing unexpected underachievement. Paper presented at the National Research Center on Learning Disabilities Responsiveness-to-Intervention Symposium, Kansas City, MO.

3. Learning Disabilities is a Construct • Does the identification model that is derived from the classification identify a unique subgroup of underachievers? • Children may be validly identified even when the underlying classification does not yield a unique subgroup: is the classification valid? • Validity of classifications only be tested on variables not used to form the classification- cognitive skills, response to intervention, neuroimaging, genetics • Validity assumes reliability Fletcher, J. M., & Denton, C. (2003, December). Validity of alternative approaches to the identification of LD: Operationalizing unexpected underachievement. Paper presented at the National Research Center on Learning Disabilities Responsiveness-to-Intervention Symposium, Kansas City, MO.

4. LD is a Valid Classification Learning disabilities are real! Stands up across definitional variation (doesn’t help identify individuals) Children and adults with different forms of LD can be reliably and validly differentiated from each other, typical achievers, and other disabilities on cognitive correlates, response to intervention, neural correlates, and heritability What happens when we apply these criteria to different classifications? Fletcher, J. M., & Denton, C. (2003, December). Validity of alternative approaches to the identification of LD: Operationalizing unexpected underachievement. Paper presented at the National Research Center on Learning Disabilities Responsiveness-to-Intervention Symposium, Kansas City, MO.

5. Alternative Classification Models 1. Different forms of discrepancy: VIQ, PIQ, Listening comprehension- reading comprehension 2. Low achievement 3. Intra- individual differences 4. Response to intervention 5. Hybrid models Fletcher, J. M., & Denton, C. (2003, December). Validity of alternative approaches to the identification of LD: Operationalizing unexpected underachievement. Paper presented at the National Research Center on Learning Disabilities Responsiveness-to-Intervention Symposium, Kansas City, MO.

6. Alternative Discrepancy Models: Discrepant vs. LA(Fletcher et al., 1994) 80% impaired under all definitions; difference is in people above the low achievement cut point, but below the regression cut point Fletcher, J. M., & Denton, C. (2003, December). Validity of alternative approaches to the identification of LD: Operationalizing unexpected underachievement. Paper presented at the National Research Center on Learning Disabilities Responsiveness-to-Intervention Symposium, Kansas City, MO.

7. Fletcher, J. M., & Denton, C. (2003, December). Validity of alternative approaches to the identification of LD: Operationalizing unexpected underachievement. Paper presented at the National Research Center on Learning Disabilities Responsiveness-to-Intervention Symposium, Kansas City, MO.

8. Low Achievement • Designate a cut point on the achievement dimension • Strengths: Strong validity, linked to intervention, easy to implement • Weaknesses: Cut point, does not measure the underlying construct (can’t differentiate subgroups of poor readers when the cause is known to be related to emotional difficulty, economic disadvantage, and inadequate instruction) • Necessary but not sufficient Fletcher, J. M., & Denton, C. (2003, December). Validity of alternative approaches to the identification of LD: Operationalizing unexpected underachievement. Paper presented at the National Research Center on Learning Disabilities Responsiveness-to-Intervention Symposium, Kansas City, MO.

9. Intra- Individual Differences Model “while IQ tests do not measure or predict a student’s response to instruction, measures of neuropsychological functioning and information processing could be included in evaluation protocols in ways that document the areas of strength and vulnerability needed to make informed decisions about eligibility for services, or more importantly, what services are needed.” Fletcher, J. M., & Denton, C. (2003, December). Validity of alternative approaches to the identification of LD: Operationalizing unexpected underachievement. Paper presented at the National Research Center on Learning Disabilities Responsiveness-to-Intervention Symposium, Kansas City, MO.

10. Intra- Individual Differences Model “An essential characteristic of SLD is failure to achieve at a level of expected performance based upon the student’s other abilities (NCLD, 2002, p. 4).” Another version of a 2 test (or more) discrepancy? Fletcher, J. M., & Denton, C. (2003, December). Validity of alternative approaches to the identification of LD: Operationalizing unexpected underachievement. Paper presented at the National Research Center on Learning Disabilities Responsiveness-to-Intervention Symposium, Kansas City, MO.

11. Biobehavioral Systems Model Fletcher, J. M., & Denton, C. (2003, December). Validity of alternative approaches to the identification of LD: Operationalizing unexpected underachievement. Paper presented at the National Research Center on Learning Disabilities Responsiveness-to-Intervention Symposium, Kansas City, MO.

12. Problems • Processing subtypes, patterns weakly related to intervention outcomes (if at all) • Not sure of what processes to measure outside word recognition • What about non- MR children with flatter profiles? (Biased towards milder impairments because severity is correlated with shape) • Perpetuates assessment model (test and treat) that has not been effective in enhancing outcomes • Difficult to scale (send all school psychologists to NP school?) • But: strong validity at achievement level (What information is added outside variation in achievement domains?) Fletcher, J. M., & Denton, C. (2003, December). Validity of alternative approaches to the identification of LD: Operationalizing unexpected underachievement. Paper presented at the National Research Center on Learning Disabilities Responsiveness-to-Intervention Symposium, Kansas City, MO.

13. Response to Intervention • Serial curriculum- based assessments of learning in relation to an intervention • Identification is more reliable than when based on a single assessment, even if the intercept is used • As one criterion, student may be LD if they do not respond to instruction that works with most other students (I.e., unexpected underachievement) • Identifies a unique subgroup of underachievers that reflects an underlying classification that can be validated (Al- Otaiba & Fuchs, 2002; Vellutino et al., 2003;) Fletcher, J. M., & Denton, C. (2003, December). Validity of alternative approaches to the identification of LD: Operationalizing unexpected underachievement. Paper presented at the National Research Center on Learning Disabilities Responsiveness-to-Intervention Symposium, Kansas City, MO.

14. What percentage of G1 children don’t respond adequately to quality intervention?(Mathes et al., 2003) Primary only: 14/90 = 16% (3% of school population) Primary + Secondary: • Proactive: 1/82 = < 1% (< .2% of school population) • Responsive: 7/83 = 8% (<1.5% of school population) (Woodcock Basic Reading < 30th percentile) Fletcher, J. M., & Denton, C. (2003, December). Validity of alternative approaches to the identification of LD: Operationalizing unexpected underachievement. Paper presented at the National Research Center on Learning Disabilities Responsiveness-to-Intervention Symposium, Kansas City, MO.

15. Severe RD before and after 8 week intervention (7- 17 years old) Simos et al. (2002) Fletcher, J. M., & Denton, C. (2003, December). Validity of alternative approaches to the identification of LD: Operationalizing unexpected underachievement. Paper presented at the National Research Center on Learning Disabilities Responsiveness-to-Intervention Symposium, Kansas City, MO.

16. Not At Risk Fletcher, J. M., & Denton, C. (2003, December). Validity of alternative approaches to the identification of LD: Operationalizing unexpected underachievement. Paper presented at the National Research Center on Learning Disabilities Responsiveness-to-Intervention Symposium, Kansas City, MO.

17. At Risk: Responders Fletcher, J. M., & Denton, C. (2003, December). Validity of alternative approaches to the identification of LD: Operationalizing unexpected underachievement. Paper presented at the National Research Center on Learning Disabilities Responsiveness-to-Intervention Symposium, Kansas City, MO.

18. At Risk: Nonresponders Fletcher, J. M., & Denton, C. (2003, December). Validity of alternative approaches to the identification of LD: Operationalizing unexpected underachievement. Paper presented at the National Research Center on Learning Disabilities Responsiveness-to-Intervention Symposium, Kansas City, MO.

19. Pre P RN Pre Pre P RN What about the Nonresponders (Grade 2 and 3)? Wave 1 Wave 2 Wave 3 Wave 4 Round 1 Phono-GraphixRead Naturally 8 weeks8 weeks8 weeks Round 2 Baseline Phono-Graphix Read Naturally 8 weeks8 weeks8 weeks Fletcher, J. M., & Denton, C. (2003, December). Validity of alternative approaches to the identification of LD: Operationalizing unexpected underachievement. Paper presented at the National Research Center on Learning Disabilities Responsiveness-to-Intervention Symposium, Kansas City, MO.

20. Woodcock-Johnson III Basic Skills Standard Scores Fletcher, J. M., & Denton, C. (2003, December). Validity of alternative approaches to the identification of LD: Operationalizing unexpected underachievement. Paper presented at the National Research Center on Learning Disabilities Responsiveness-to-Intervention Symposium, Kansas City, MO.

21. Gray Oral Reading Test Fluency Standard Scores Fletcher, J. M., & Denton, C. (2003, December). Validity of alternative approaches to the identification of LD: Operationalizing unexpected underachievement. Paper presented at the National Research Center on Learning Disabilities Responsiveness-to-Intervention Symposium, Kansas City, MO.

22. Gray Oral Reading Test Comprehension Fletcher, J. M., & Denton, C. (2003, December). Validity of alternative approaches to the identification of LD: Operationalizing unexpected underachievement. Paper presented at the National Research Center on Learning Disabilities Responsiveness-to-Intervention Symposium, Kansas City, MO.

23. Fletcher, J. M., & Denton, C. (2003, December). Validity of alternative approaches to the identification of LD: Operationalizing unexpected underachievement. Paper presented at the National Research Center on Learning Disabilities Responsiveness-to-Intervention Symposium, Kansas City, MO.

24. Problems • What is the best cut point? (index to benchmarks, growth, norm referenced scores: probably makes little difference if measurement error taken into account; don’t make it a formula) • Scaling and implementation: problem is not with the research base, but with its scaling (so what else is new? 30 years later we still can’t do IQ discrepancy correctly) • Necessary but not sufficient: needs additional criteria Fletcher, J. M., & Denton, C. (2003, December). Validity of alternative approaches to the identification of LD: Operationalizing unexpected underachievement. Paper presented at the National Research Center on Learning Disabilities Responsiveness-to-Intervention Symposium, Kansas City, MO.

25. OSEP LD Summit: Hybrid Model • 1. Low Achievement • 2. Apply the Exclusions • 3. Evaluate Response to Intervention (maintain flexibility of the interdisciplinary team) Unlike other alternative models, may yield a valid classification of unexpected underachievers Fletcher, J. M., & Denton, C. (2003, December). Validity of alternative approaches to the identification of LD: Operationalizing unexpected underachievement. Paper presented at the National Research Center on Learning Disabilities Responsiveness-to-Intervention Symposium, Kansas City, MO.