Reading difficulties: Research and treatment Associate Professor Genevieve McArthur ARC Australian Research Fellow (Macquarie Centre for Cognitive Science) ARC Centre for Cognition and its Disorders

Making evidence-based decisions about the diagnosis and treatment of dyslexia

Outline The importance of reviewing the scientific evidence: Data collection The diagnosis of dyslexia different ways to diagnosis of dyslexia myths about dyslexia how to make an evidence-based diagnosis of dyslexia Treatments for dyslexia how to make an evidence-based decision about treatment “causal” treatments reading treatments The importance of reviewing the scientific evidence: The Results

The importance of scientific evidence Which of these statements – commonly made in the media – are supported by the weight of scientific evidence? True = 1 False = 2 You should floss your teeth to reduce tooth decay and gum disease You should take a regular dose of vitamin C to prevent colds You should get a flu shot You should reduce your salt intake to improve your blood pressure You should eat a high-fibre diet to prevent colon cancer You should take gingko to prevent dementia You should drink at least eight glasses of water per day (tea and coffee does not count) You should drink red wine - but not white wine or beer You should stretch before or after exercise to prevent muscle soreness

✓ Outline The importance of scientific evidence: Data collection The diagnosis of dyslexia different ways to diagnosis of dyslexia myths about dyslexia how to make an evidence-based diagnosis of dyslexia Treatments for dyslexia how to make an evidence-based decision about treatment “causal” treatments reading treatments The importance of scientific evidence: The Results

Different ways to diagnose dyslexia Research DSM4 Response to Intervention Descriptive What is impaired? Reading Sensation ~ Academia Everyday reading Response to intervention What is unimpaired? NVIQ Sensation Education Neurology Language ~ IQ Diagnostic tests Hearing Vision Education history

Myths about dyslexia More boys than girls have dyslexia If you reverse letters (d for b or p) then you have dyslexia People with dyslexia are more likely to be left-handed People with dyslexia are unusually intelligent People with dyslexia are unusually artistic

So … how are you supposed to diagnose dyslexia?

Use an evidence-based model of reading

 8007  P D D L  B-O-O-T ‘p’ ‘u’ ‘b’ ‘b’ ‘oot’ ‘fruit’ regular words: BOOT See word Letter identification 1  8007 BOOT  P D D L B O O T Letter identification 2  B-O-O-T B-OO-T Parsing ‘p’ ‘u’ ‘b’ ‘b’ ‘oo’ ‘t’ Letter-sounds ‘b’ ‘oot’ ‘boot’ Blending ‘fruit’ ‘boot’ Spoken word planning ‘boot’ Spoken word production

b oo k  ‘book’  ‘book’ “book” irregular words: BOOK See word Letter identification 1 BOOK B O O K Letter identification 2 BOOK Written word rep B-OO-K Parsing ‘book’ Spoken word rep ’ b oo k Letter-sounds Meaning ’  ‘book’ Blending  ‘book’ Spoken word planning ‘book’ “book” Spoken word production “book”

to read regular and irregular words you need: two reading routes that work at the same time that work equally well See word Spoken word production Letter identification 1 Letter identification 2 Parsing Letter-sounds Blending Spoken word planning Written word rep Spoken word rep Word meaning Sight-word Lexical Nonlexical Phonics

but sometimes they don’t: See word Spoken word production Letter identification 1 Letter identification 2 Parsing Letter-sounds Blending Spoken word planning Written word rep Spoken word rep Word meaning Sight-word Lexical Nonlexical Phonics some good at sight-word reading (lexical) but bad at phonics reading (nonlexical) = phonological dyslexia but bad at sight-word reading (lexical)= surface dyslexia some good at phonics reading (nonlexical) many bad at sight-word reading (lexical) and bad at phonics reading (nonlexical)= mixed dyslexia

✗ ✗ ✗ need to assess: two reading routes CC2 www.motif.org.au See word Spoken word production Letter identification 1 Letter identification 2 Parsing Letter-sounds Blending Spoken word planning Written word rep Spoken word rep Word meaning Sight-word Lexical Nonlexical Phonics each component Irregular-word Reading CC2 Non-word Reading CC2 ✗ ✗ ✗

✓ ✓ Outline The importance of scientific evidence: Data collection The diagnosis of dyslexia different ways to diagnosis of dyslexia myths about dyslexia how to make an evidence-based diagnosis of dyslexia Treatments for dyslexia “causal” and reading treatments how to make an evidence-based decision about treatment an evaluation of “causal” and reading treatments The importance of scientific evidence: The Results ✓

Commercial treatments for dyslexia “Causal” treatments Reading treatments

Introductions to evidence-based decisions about treatment Ben Goldacre http://www.youtube.com/watch?v=O1Q3jZw4FGs Dorothy Bishop dystalk.com/talks/60-evaluating-alternative-solutions-for-dyslexia

Step 1: Find a systematic review Review of all properly controlled studies of a treatment Done by an independent expert not a journalist not a private company not connected with the company (e.g., Rod Nicolson and Dore) Some sources Cochrane Reviews Google Scholar Google What Works Clearinghouse ~ MUSEC Briefings

Step 2: DIY systematic review control group no control group Significantly bigger reading gains in treated group than control group No difference in reading gains in treated and control groups Large gains in reading scores in the treated group Small gains in reading scores in the treated group Coltheart, M., & McArthur, G. M. (In Press). Neuroscience, education and educational efficacy research. In M. Anderson and S. D.Sala (Eds.), Education in Neuroscience Oxford, UK: Oxford University Press. http://deevybee.blogspot.com/2010/08/three-ways-to-improve-cognitive-test.html

Step 3: Use indirect evidence e.g. Eye Q > reading Evidence that the same type of treatment (other brand) improves reading Evidence that the treatment itself (Eye Q) improves a factor (fatty acids) that has been scientifically proven to improve reading Evidence that the same type of treatment (other brand) improves a factor (fatty acids) that has been scientifically proven to improve reading Coltheart, M., & McArthur, G. M. (In Press). Neuroscience, education and educational efficacy research. In M. Anderson and S. D.Sala (Eds.), Education in Neuroscience Oxford, UK: Oxford University Press.

Step 4: Ignore brain data Brain data cannot tell us if an educational treatment works or not Focus on the behavioural evidence (i.e., reading behaviour) If a program did not improve reading but did change the brain, would you pay good money to buy it? If a program did improve reading but did not change the brain, would you not buy it? Coltheart, M., & McArthur, G. M. (In Press). Neuroscience, education and educational efficacy research. In M. Anderson and S. D.Sala (Eds.), Education in Neuroscience Oxford, UK: Oxford University Press.

Step 5: Ignore anecdotes Biased sample Subjective data Cognitive dissonance Coltheart, M., & McArthur, G. M. (In Press). Neuroscience, education and educational efficacy research. In M. Anderson and S. D.Sala (Eds.), Education in Neuroscience Oxford, UK: Oxford University Press.

Commercial treatments for dyslexia “Causal” treatments Reading treatments

Program 1. Systematic review 2. DIY review 3. Indirect evidence NA 2 studies Reading not tested The effect of PA on reading contentious Strong et al. 2010 ~ 10 studies No effect Hyatt et al. 2009 A few studies Bishop 2007 Working memory can be trained but its effect on reading unknown Hyatt 2007 A few studies

Program 1. Systematic review 2. DIY review 3. Indirect evidence NA Phonics has small to moderate effect on dyslexia WWC A few studies Small effect

✓ ✓ ✓ Outline The importance of scientific evidence: Data collection The diagnosis of dyslexia different ways to diagnosis of dyslexia myths about dyslexia how to make an evidence-based diagnosis of dyslexia Treatments for dyslexia how to make an evidence-based decision about treatment “causal” treatments reading treatments The importance of scientific evidence: The Results ✓ ✓

The importance of evidence: The evidence Which of these statements – commonly made by the media – are supported by the weight of scientific evidence? True = 1 False = 2 1. You should floss your teeth to reduce tooth decay and gum disease 2. You should take a regular dose of vitamin C to prevent colds 3. You should get a flu shot 4. You should reduce your salt intake to improve your blood pressure 5. You should eat a high-fibre diet to prevent colon cancer 6. You should take gingko to prevent dementia 7. You should drink at least eight glasses of water per day (tea and coffee does not count) 8. You should drink red wine - but not white wine or beer 9. You should stretch before or after exercise to prevent muscle soreness ✗ ✗ ✗ ✗ ✗ ✗ ✗ ✗ ✗

This above all: to the scientific evidence be true, and it must follow, as the night the day, thou are less likely to be false to any man (or woman or child) (Shakespeare … kind of)

Thank you