Anne Castles and Genevieve McArthurUNDERSTANDING DYSLEXIA

When reading failsto develop normally

• No child will learn to read without appropriate conditions

• But some children (10 - 15%) fail despite:– No obvious neurological or sensory impairment– Supportive environment

• “Dyslexia” or “specific learning disability”

How do we detect this in theclassroom?

Using Response to Interventionin the diagnosis

• Some of the children at the bottom of the distribution may be “instructional casualties”

• We can identify these through the Response to Intervention model:– Do they respond to intensive intervention?– Or are they still here…

Reading difficulty or “dyslexia”

Profiles of dyslexia

• As reading involves many processes, would not expect it always to fail in the same way

• Different profiles depending on which subskill has not developed normally

• Need to have a model of reading to guide diagnosis and assessment

Letter-Sound Route

Dictionary Look-Up Route

What is needed for assessment?

• Determine whether a student is reading at the level expected for age

• Test all aspects of reading, without over‐testing children that have no problems!

What is needed for assessment?

1. Test of single word reading aloud (with normative data)– Irregular words (yacht)

What is needed?

1. Test of single word reading aloud (with normative data)– Irregular words (yacht)

2. Test of nonword reading aloud

What is needed for assessment?

1. Test of single word reading aloud (with normative data)– Irregular words

(yacht)2. Test of nonword reading aloud3. Test of Reading Comprehension

What is needed for assessment?

• Based on these results can then “drill down” further

• Use as a basis for a targeted treatment

Motif.org.au

1. Test of single word reading

• Castles and Coltheart 2• Set of 40 regular, irregular and non-words– Each scored separately

• Stopping rule• Normed on 1000 Australian children yrs 1-6

Motif.org.au

2. Test of Reading Comprehension

• TERC: Test of Everyday Reading Comprehension• 10 everyday reading tasks increasing in difficulty– Text screen– Canteen menu– Shopping list

• Each followed by two comprehension questions• Two forms (A and B)

Motif.org.au

Intervention

Intervention

Phonics

• Ability to learn new words using the “letter‐sound” rules

• SHIP “sh” “i” “p” “ship” • Systematic review and meta-analyses – Ehri et al. (2000)– Suggate (2010) – McArthur, Castles et al. (2012)

• Moderate to large significant effects on poor phonics skills

Intervention

Intervention

Sight word training

• Ability to learn to recognise whole words by sight • Particularly important for words that break letter-sound

rules• YACHT “y” “a” “ch” “t” “yacht” • YACHT “y” “o” “t” “yot” • Two controlled trials of sight word training on poor

readers – McArthur, Castles et al. (2013)– McArthur, Castles et al. (in preparation)

• Large and significant effects on poor sight word accuracy

Intervention

Intervention

Language training

• Knowing the meaning of words and how they are said are spoken language skills that are used during reading

• Evidence that spoken language training has moderate to large effects on phonological and expressive language skills– Law et al. (2004)– Cirrin & Gillam (2008)– Ebbels (2014)

• Spoken language training is typically carried out by speech and language therapists

Intervention

Commercial Interventions

Evidence based decisions• Teach teachers how to make evidence based decision ‐

about any intervention for poor readers (easier than it sounds)

• Provide online site that provides evidence-based decisions (and evidence) for interventions for poor readers (even easier)

• Inspire teachers to choose evidence-based interventions – Provide funding for evidence-based interventions on online site– Schools provide scientific evidence for an intervention to get

funding – This intervention and evidence added to above online site