Evaluation of a Reading Tutor with Synthesized Speech Feedback for Dutch Speaking Elementary School Children with Reading Difficulties

Leen Cleuren Lukas Latacz Yuk On Kong Maaike Vandermosten Werner Verhelst Hugo Van hamme Pol Ghesquière 1

Introduction

• Children with reading difficulties (RD) in Dutch – Dutch is an orthographic transparent language: grapheme-to phoneme-rules are much more consistent than in English – RD are characterized by speed problems, rather than accuracy problems • Early, regular and adequate intervention needed – To support reading development – To support appropriate functioning in all school domains 2

Introduction

• Intervention to speed up reading?

– Not focused on phonological skills (e.g.; knowing how to split up a word in its constituent phonemes)  improves accuracy but not speed – Focused on … READING READING READING!!

(To overcome the ‘Matthew effect’) – What kind of reading?

 still subject of discussion 3

Introduction

• A general intervention approach

Let children read aloud under supervision Give feedback on what they read

– Repetitive versus non-repetitive strategies • Repeated reading: read the same passage over and over again until a preset criterion is reached • Wide reading: no rereadings, always new reading material – Different feedback techniques • General feedback: indicates whether ‘performance’ is right or wrong • Corrective feedback: idem + provides help to correct the error 4

Introduction

•

Daily

reading practice necessary – Not always possible due to classroom issues and governmental health insurance constraints – A computerized reading intervention program could offer a welcome solution  error detection and child tracking: speech recognition  feedback and decoding assistance: synthesized/digitized speech + ability to highlight words or word parts = SPACE project Speech Algorithms for Clinical and Educational applications 5

Remark

• Synthesized versus digitized speech

Digitized speech

sounds like recorded speech; it is speech that is converted into a digitized format and then reconverted back into speech.

Synthesized speech

is computer generated speech that is created by concatenating pieces of recorded speech that are stored in a database, based on various acoustic/phonetic algorithms.

Programs can be ‘open’ so that its user is not restricted to the learning material chosen and implemented by the authors of the program.

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Present Study

• Evaluation of the Dutch Reading Tutor with synthesized speech feedback developed within the SPACE project

Can substantial improvements in reading accuracy and speed be obtained in reading disabled elementary school children that used the SPACE Reading Tutor?

 intervention study – Instructional-level non-repetitive text reading – Corrective phoneme-by-phoneme feedback e.g., speelgoed 7

Participants

• 10 pairs of 2nd – 6th grade elementary school children • Normal IQ, Dutch speaking, normal vision and hearing • 8 girls + 12 boys • Age range: 6.75-10.75 years • Individual matching on chronological age, IQ, mastery text reading level (AVI)  no significant group differences (

p

s > .10) 8

Pre- and Posttest Materials

• Paper-and-pencil tests – One-Minute-Test: 1 list of words – Klepel: 1 list of pseudowords – AVI test: stories • Computerized tests – Real Word Reading Test: 3 lists of words – PseudoWord Reading Test: 3 lists of pseudowords – Story Reading Test: stories accuracy and speed independently registered 1-syl, 2-syl, 3+4-syl (pseudo)words separately assessed 3 stories at mastery, instructional and frustrational level 9

Intervention

• Instructional-level stories (commercial reading materials) • Presented on a touch screen, paragraph-by-paragraph • No re-readings, always new reading material • Wizard-of-Oz-method: no computer speech recognition • Help for a word: child touches word and receives phoneme-by-phoneme feedback • Errors: erroneous word highlighted + phoneme-by phoneme feedback, child asked to blend phonemes together 10

/k/ /w/ /a/ /t/ Herhaal jij het woord ook eens? En dan mag je verder gaan.

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• Example: Boy, 2 nd grade, Instructional level = AVI1 poes kijkt naar de boom.

daar zit nog een poes.

op een tak, heel hoog.

jan ziet lien. lien woont hier pas. ze zoekt haar poes. dag, zegt lien. hoe heet jij? ik ben jan, zegt jan. lien kijkt naar de poes op het hek. 12

Design

• Randomized pretest-posttest matched-group design – Matched pairs randomly assigned to intervention or control group pretest intervention intervention posttest follow up week 1 week 2 + 3 week 4 week 5 + 6 week 7 – 20-minute reading sessions; 4.5 hours of training in total week 11 13

Motivation

• Improvement graph after each session • Verbal encouragement by the Reading Tutor • Stickers that could be exchanged for a present at the end of the study 14

Analysis Strategy

• Effects of intervention – Mixed model analyses of covariance (ANCOVA) • Pretest of each variable: covariate • ‘Matched pair’: random factor • Intervention-Control: between-subjects factor – Measure of effect size: R² • Influence of performance level on intervention effects – Why? Because not all children obtained a ‘clinical’ pretest OMT and Klepel score – Therefore: Clinical Average – How?

• Intervention-Control: effect allowed to vary at pair level • ‘group*performance’ added to the fixed part of the original model 15

Results

• Feedback: use of synthesized speech  speech synthesis was good: sounded naturally, was clearly audible and well understandable  children got quickly used to the reading tutor’s voice and were very understanding w.r.t. occasional mistakes 16

Real Word Reading Results

Real Word Accuracy Variables

8 2 0 6 4 18 16 14 12 10

p

= .15;

R²

= .10

C I OMT-Standard score

p

= .003;

R² p

= .17

= .04;

p R²

= .19

= .15;

R²

= .20

p

C I RWRT_1syl-Errors C I RWRT_2syl-Errors Pretest Posttest Follow-up C I RWRT_3+4syl-Errors 17

Real Word Reading Results

180 160 140 120 100 80 60 40 20 0

p

= .16;

R² p

= .43

= .32;

R²

Real Word Speed Variables

p

= .11;

p R²

= .29

= .15;

R²

= .20

= .58

C I RWRT_1syl-Time C I RWRT_2syl-Time Pretest Posttest Follow-up C I RWRT_3+4syl-Time 18

PseudoWord Reading Results

Pseudoword Accuracy Variables

p

= .05;

R²

= .40

80 70 60 50 40 30 20 10 0 C I Klepel-Standard score

p

= .07;

R²

= .37

p

= .16;

R²

= .23

C I PWRT_1syl-Errors C I PWRT_2syl-Errors Pretest Posttest Follow-up C I PWRT_3+4syl-Errors 19

250 200 150 100 50 0

PseudoWord Reading Results

Pseudoword Speed Variables

p

= .01;

R²

= .55

p

= .01;

R²

= .57

Clinical children: p

= .03;

p R²

= .01

= .46

C I PWRT_1syl-Time C I PWRT_2syl-Time Pretest Posttest Follow-up C I PWRT_3+4syl-Time 20

Story Reading Results

15 10 5 30 25 20 0

p p

Story Accuracy Variables

= .30;

R²

= .14

= .01;

R² p

= .61

= .11;

R²

= .19

C I AVI-Mastery level* C I SRT_Mastery-Errors C I SRT_Instructional Errors Pretest Posttest Follow-Up

Average children: p

= .03

C I SRT_Frustrational Errors 21

Story Reading Results

Average children: p

= .23;

p R²

= .01

= .20

Story Speed Variables

200 180 160 140 120 100 80 60 40 20 0 C I SRT_Mastery-Time C I SRT_Instructional-Time Pretest Posttest Follow-up C I SRT_Frustrational-Time 22

Summary

• Aim of intervention study: investigate whether improvements in reading accuracy and reading speed could be obtained in reading disabled Dutch speaking elementary school children that used the SPACE Reading Tutor with synthesized speech feedback • Design: randomized pretest-posttest (-posttest) matched-group design in which each child of a matched pair was randomly assigned to an intervention or control group • Intervention: individualized intervention sessions focused on non-repetitive instructional-level text reading with phoneme-by-phoneme feedback when an error was made or help was asked for 23

Summary

• Reading accuracy – Posttest intervention > control: 1syl + 2syl real words, instructional level stories average children: intervention > control: 3+4syl real words – Follow-up intervention > control: 1syl + 2syl real words, 1syl + 2syl + 3+4syl pseudowords, OMT SS average children: intervention > control: 3+4syl real words, frustrational level stories – 1 counter-intuitive result at both posttest and follow-up!

intervention < control: mastery level stories  suggestions?

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Summary

• Reading speed – Posttest intervention > control: 1syl + 2syl real words average children: intervention > control: frustrational level stories – Follow-up intervention > control: 1syl + 2syl real words – 1 counter-intuitive result at follow-up!

intervention < control: 1syl + 2syl + 3+4syl pseudowords  explanation found 25

Conclusion

• Despite a very limited amount of training (

M

= 4.5 hours), beneficial influence of extra-curriculum practice with the SPACE Reading tutor on the reading performance of elementary school children, mainly w.r.t word and pseudoword reading!.

• Both clinical and average performing children benefit from exercising with the Reading Tutor.

• Gains obtained for both reading accuracy and speed.

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Thank You

• For listening!

• To Lukas Latacz (VUB), Yuk On Kong (VUB), Werner Verhelst (VUB), Hugo Van hamme (KUL, ESAT), Pol Ghesquière (KUL, ORTHO) • Questions?

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