Article review

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VanDerMeer26Rispoli2C2010.pdf

informa healthcare Developmental Neurorehabilitation, August 2010; 13(4): 294–306

SUBJECT REVIEW

Communication interventions involving speech-generating devices for children with autism: A review of the literature

LARAH A. J. VAN DER MEER1 & MANDY RISPOLI2

1Victoria University of Wellington, Wellington, New Zealand and 2Texas A & M University, College Station, TX, USA

(Received 1 February 2010; accepted 1 February 2010)

Abstract Objective: The current review synthesizes communication intervention studies that involved the use of speech-generating devices (SGD) for children with autism. Methods: Twenty-three studies were identified that met the inclusion criteria following systematic searches of electronic databases, journals and reference lists. Studies were evaluated in terms of: (a) participants, (b) setting, (c) mode of communication, (d) communication skill(s) taught to the participant, (e) intervention procedures, (f) outcomes, (g) follow-up and generalization, (h) reliability and treatment integrity and (i) design and certainty of evidence. Results: Intervention, most commonly targeting requesting skills, was provided to a total of 51 children aged 3–16 years. Intervention strategies followed two main approaches: operant/behavioural techniques and naturalistic teaching procedures. Positive outcomes were reported for 86% of the studies and 78% of the studies were categorized as providing conclusive evidence. Conclusion: The literature base suggests that SGDs are viable communication options for children with autism. However, several areas warrant future research.

Keywords: autism, ASD, speech generating device, voice-output communication aid, communication, intervention

Resumen Objetivo: La actual revisión sintetiza los estudios sobre intervenciones de comunicación que utilizan dispositivos de generación del habla (SGD) para niños con autismo. Métodos: Posterior a una búsqueda sistematizada de listas de referencias, revistas y bases de datos electrónicas se identificaron veintitrés estudios que cumplı́an con los criterios de inclusión. Los estudios fueron evaluados en términos de: (a) participantes, (b) escenario, (c) medio de comunicación, (d) habilidad(es) de comunicación enseñadas a los participantes,

˜os con autismo. Sin

´n de producción de la voz,

stereotyped behaviour patterns [1]. Up to half of autism do not develop speech or

develop only limited speech and language abilities these children may rely on

behaviours, including pointing,

(e) procedimiento de intervención, (f) resultados, (g) seguimiento y generalización, (h) integridad y confiabilidad del tratamiento y (i) diseño y certeza de la evidencia. Resultados: Se proporcionó intervención, con mayor interés en las habilidades de petición, a un total de 51 niños con edades comprendidas entre los 3 y los 16 años de edad. Las estrategias de intervención siguieron dos enfoques principalmente: técnicas operantes/conductuales y el enfoque de enseñanza naturalista. Se reportaron resultados positivos en el 86% de los estudios y el 78% de los estudios se categorizaron como aportadores de pruebas concluyente. Conclusión: Esta literatura de base sugiere que los SGD son una opción viable de comunicación para nin embargo, múltiples áreas ameritan una mayor investigación.

Palabras clave: autismo, ASD, dispositivos de generación del habla, dispositivo de ayuda de comunicacio comunicación, intervención

Introduction

Individuals with Autism Spectrum Disorders (ASD) children with are characterized by having significant impairments in social interaction, communication development [2–6]. Instead and the presence of restricted, repetitive and pre-linguistic

Correspondence: Larah van der Meer, School of Educational Psychology, Victoria University of Wellington, PO Box 17-310, Karori 6147, Wellington, New Zealand. E-mail: [email protected]

ISSN 1751–8423 print/ISSN 1751–8431 online/10/040294–13 � 2010 Informa UK Ltd. DOI: 10.3109/17518421003671494

reaching, eye-gazing and other facial expressions [7, 8]. Some children may also demonstrate challenging behaviour, such as aggression, tantrums and self-injury in an attempt to communicate their wants and needs [9, 10]. Such pre-linguistic behaviours become frustrating for both the commu- nicator and the communication partner, as they are often difficult to interpret.

Romski et al. [11] explained that it is unclear whether children who lack speech at a young age will remain at this pre-linguistic level. Instead the child’s communication status may change over time as a function of maturity, intervention or both. One intervention that these children may benefit from is augmentative and alternative communication (AAC). AAC refers to a practice that aims to supplement (i.e. augment) or replace (i.e. alternative) natural speech [12–15]. This is achieved either by unaided approaches, such as gestures or manual signing; or by aided systems, involving graphics (traditional orthography, photographs or line drawings). Aided systems use external equipment with a communicative function, such as Picture Exchange (PE) [16, 17] or Speech-Generating Devices (SGDs), otherwise referred to as voice output communication aids (VOCAs) [18].

In particular SGDs became prominent communi- cation options for many individuals with autism by the 1980s and 1990s [19, 20]. A SGD is a portable electronic devise that will produce either digitized or synthesized speech output. The SGD displays a variety of graphic symbols to represent a message that is activated resulting in voice output when the individual uses a finger, hand or some other means to select the message [7].

To date SGD intervention research has typically involved teaching the individual to request access to highly preferred items [18, 21]. For example, in a SGD intervention the individual might be taught to touch a picture or line drawing on the electronic speech output device, which produces a pre- recorded message, such as ‘I want __’. In return the communication partner will deliver the requested item [22]. In addition to requesting, a number of other communicative functions, such as comment- ing, greeting or answering questions would be important to teach to individuals with ASD [23]. Most of these communication skills have been taught within a positivist behaviour analytic approach using operant methods such as discrete trial training [24]. However, recently naturalistic approaches to teach- ing SGD use have been increasing [25].

Depending on communicative goals, a large variety of SGDs can be selected and customized for inter- vention. SGDs can vary in design including perma- nence of the display (static or dynamic), number of graphic representations on the display and size of the

Communication interventions 295

graphic symbols [26]. Consideration of the type of voice-output used (digitized vs synthesized) can also be important. For example, it has been hypothesized that the lack of variability and robotic nature of synthesized speech may need to be considered when implementing AAC with individuals with autism [27]. The voice-output feature of SGDs might also make this a more readily understood mode of communication, thus promoting greater community inclusion and participation [28].

An emerging corpus of intervention research has investigated the use of SGDs as well as AAC in general with individuals with developmental disabilities or autism and there are several reviews that have focused on a number of issues related to this topic [7, 18, 19, 27, 29, 30]. Schlosser and Lee [29], for example, provide support for the use of AAC in general, but did not focus on individual modalities of AAC, such as SGDs. Lancioni et al. [18] focused on the use of SGDs and PECs in teaching requesting behaviours to individuals with developmental disabilities. They concluded that outcomes are encouraging, but methodological concerns provide reason for results to be interpreted with caution. Only Schlosser et al. [19] appear to specifically review research assessing the use of SGDs for individuals with autism. Thus, in order to answer empirical questions that remain in this field [31], a systematic review of SGD interventions with individuals with autism is warranted. The aim of the current report is to systematically review the litera- ture in this field and thereby evaluate whether there is evidence to support that children with autism are capable of learning to use an SGD to communicate. Specific objectives are to provide an up-to-date synthesis of the literature in order to (a) assist clinicians in their practice of improving the commu- nication of children with autism and (b) identify gaps in the literature and areas in need of further research. Together these objectives may help to guide and inform evidence-based practice with respect to the use of SGDs in communication interventions for children with autism.

Method

Search procedures

Systematic searches were conducted in six electronic databases: Cumulative Index of Nursing and Allied Health Literatures (CINAHL), Education Resources Information Center (ERIC), Medline, Linguistics and Language Behavior Abstracts (LLBA), Proquest and PsycINFO. Publication year was not restricted, but the search was limited to English-language journal articles. The search covered all dates covered by these databases up to September 2009.

296 L. A. J. van der Meer & M. Rispoli

For the CINAHL search, voice-output communi- cation aid (or speech-generating device) and autism was entered into the All Text field. For the remaining databases, the free-text terms voice-output commu- nication aid (or VOCA or speech-generating device) and autism (or autism spectrum disorders) were inserted into the Keywords field. Abstracts of the records returned from these electronic searches were reviewed to identify studies for inclusion in the review (see Inclusion and Exclusion Criteria).

Three additional search strategies were used in order to find other possibly relevant studies that may have been missed by the electronic search. First, the reference lists for the included studies were reviewed to identify additional articles for possible inclusion. Secondly, hand searches were completed for the journals that had published the included studies. Finally, using an author search, the five databases were searched again for additional related work by authors of the studies that met the inclusion criteria. From this combination of search procedures, 25 articles were identified for possible inclusion in the systematic review.

Inclusion and exclusion criteria

To be included in this review, the article had to be a research study that included children (518 years of age) with ASD and examined the effects of an intervention involving SGDs. Intervention was defined as implementing one or more therapeutic/ teaching procedures for the purpose of trying to increase or improve the child’s communication skills or abilities through the use of a SGD. Examples could include teaching a child to use an SGD to (a) make requests, (b) spell words or (c) repair a communicative breakdown.

The research study had to obtain empirical data from which one could assess the success of the intervention. For example, a paper by Light et al. [32] initially identified for inclusion used case reports that did not provide objective data on SGD use and was therefore not included in the current review. Studies that focused only on the description of or assessment of communication skills were not included.

Data extraction

Each study identified was first evaluated to establish if it met the pre-determined inclusion criteria. All studies that met the inclusion criteria were then coded in terms of: (a) participants (e.g. age, gender, number and diagnosis), (b) setting (e.g. school, home or community setting), (c) mode of commu- nication (e.g. type of SGD used), (d) communica- tion skill(s) taught to the participant, (e) intervention procedures (e.g. least to most prompting), (f)

outcomes of the intervention, (g) follow-up and generalization, if any, (h) reliability and treatment integrity and (i) experimental design and certainty of evidence. The certainty of evidence was rated as either conclusive or inconclusive [33, 34] in order to provide an overview of the quality of the evidence across the studies reviewed [35].

Inter-rater agreement

The initial search of the six databases revealed 15 articles that met the inclusion criteria for this review. Three articles were identified in the reference list search; three articles were identified in the journal search and finally three articles were identi- fied in the author search, resulting in a total of 24 articles for inclusion in this review. To assess inter-rater agreement, an independent rater reviewed these 24 articles according to the inclusion criteria. This resulted in 100% agreement for the initial three search methods. However, one discrepancy was identified in the author search. Upon review, this study [6] was excluded because the participant did not have a formal ASD diagnosis. Therefore, a total of 23 articles met the inclusion criteria.

Results

A total of 29 interventions/experiments were reported in the 23 included studies. Table I sum- marizes the purpose, participants, type of SGD, outcomes and design and certainty of evidence for each of the 23 included studies.

Participants

A total of 51 participants with ASD were included in the studies. When a study included participants with and without an ASD diagnosis, only data from the ASD participants were coded. Of these 51 participants, 90.2% (n ¼ 46) were boys and 9.8% (n ¼ 5) were girls, a ratio of nine boys to every girl. The majority of participants were reported as having autism (n ¼ 34, 66.7%), five as having ASD (9.8%) and 12 (23.5%) with pervasive developmental disorder–not otherwise specified (PDD-NOS). Of those with autism or ASD, diagnosis ranged from mild-to-severe and included Autistic disorder. Thirty-seven per cent of participants (n ¼ 19) also had a dual diagnosis of ASD and some level of intellectual disability or other developmental delay [10, 36–43]. In one study [24] the sole participant had a diagnosis of Down syndrome and Autistic disorder.

Ages ranged from 3–16 years (mean ¼ 7.7). In one study [44] age was not specifically identified, instead it was stated that participants were pre-school aged.

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w as

s u

p p

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il d

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d id

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t h

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f o r

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d if

fe re

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m es

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C o n

cl u

si ve

: A

lt er

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in g

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T w

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C o n

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b as

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p ar

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p an

ts d

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n

C o n

cl u

si ve

: S

tu d

y 1 :

co m

- b

in ed

m u

lt ie

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an d

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n ;

S tu

d y

2 :

m u

lt ip

le b

as el

in e

ac ro

ss

tw o s

et ti

n gs

C o n

cl u

si ve

: M

u lt

ip le

b as

e- li n

e si

n gl

e- ca

se e

xp er

i- m

en ta

l d

es ig

n a

cr o ss

st

u d

en t

an d

t ea

ch er

p

ar ti

ci p

an ts

C o n

cl u

si ve

: M

u lt

ip le

p ro

b e

ac ro

ss p

ar ti

ci p

an ts

d es

ig n

C o n

cl u

si ve

: M

u lt

ip le

p ro

b e

d es

ig n

a cr

o ss

f o u

r ac

ti vi

ti es

C o n

cl u

si ve

: M

u lt

ip le

p ro

b e

d es

ig n

a cr

o ss

t im

e an

d

ro u

ti n

es

Communication interventions 297

(c on

ti n u ed

)

T ab

le I

. C

o n

ti n

u ed

.

D es

ig n

a n

d c

er ta

in ty

o f

S tu

d y

P u

rp o se

P

ar ti

ci p

an ts

S

G D

( sp

ee ch

t yp

e)

O u

tc o m

es

ev id

en ce

S ch

lo ss

er

et

al .

T o e

xa m

in e

th e

ef fe

ct s

o f

sy n

th et

ic s

p ee

ch

1 b

o y,

w it

h a

u ti

sm

L ig

h tW

R IT

E R

S L

D

u ri

n g

b as

el in

e p

er fo

rm an

ce w

as a

t 0 %

, d

u ri

n g

C o n

cl u

si ve

: A

d ap

te d

a lt

er -

[3 7 ]

o u

tp u

t an

d o

rt h

o gr

ap h

ic f

ee d

b ac

k o n

s p

el li n

g (1

0 y

ea rs

) 3 5 ;

te xt

-t o -

tr ai

n in

g th

e p

er ce

n ta

ge o

f w

o rd

s sp

el le

d

n at

in g

tr ea

tm en

ts d

es ig

n

sp ee

ch s

yn th

et ic

co

rr ec

tl y

ro se

t o c

ri te

ri o n

a n

d d

u ri

n g

m ai

n -

sp ee

ch o

u tp

u t

te n

an ce

p er

ce n

ta ge

o f

w o rd

s sp

el le

d c

o rr

ec tl

y (D

E C

ta lk

), w

it h

re

m ai

n ed

h ig

h a

cr o ss

c o n

d it

io n

s. T

h e

sa m

e a

Q W

E R

T Y

o cc

u rr

ed f o r

co rr

ec t

le tt

er s

eq u

en ce

s u

n d

er a

ll

ke yb

o ar

d

th re

e co

n d

it io

n s.

S p

ee ch

o u

tp u

t al

o n

e an

d i

n

co m

b in

at io

n w

it h

o rt

h o gr

ap h

ic f

ee d

b ac

k re

su lt

ed i

n m

o re

e ff

ic ie

n t

sp el

li n

g th

an

o rt

h o gr

ap h

ic f

ee d

b ac

k al

o n

e S

ch lo

ss er

an

d

T o s

ys te

m at

ic al

ly r

ep li ca

te S

ch lo

ss er

e t

al .’

s [3

7 ]

4 b

o ys

, w

it h

m il d

– L

ig h

tW R

IT E

R -S

- P

ar ti

ci p

an ts

r ea

ch ed

c ri

te ri

o n

( co

rr ec

t sp

el li n

g)

C o n

cl u

si ve

: A

d ap

te d

a lt

er -

B li sc

h ak

[ 5 0 ]

st u

d y

in o

rd er

t o d

et er

m in

e th

e ef

fe ct

s o f

m o d

er at

e au

ti sm

L

3 5 ;

sy n

th et

ic

ac ro

ss a

ll t

h re

e fe

ed b

ac k

co n

d it

io n

s.

n at

in g

tr ea

tm en

ts d

es ig

n

sy n

th et

ic s

p ee

ch a

n d

p ri

n t

fe ed

b ac

k o n

(8

–1 2 y

ea rs

) sp

ee ch

E

ff ic

ie n

cy d

at a

va ri

ed f

ro m

t h

e p

re li m

in ar

y (w

it h

t h

re e

in st

ru ct

io n

al sp

el li n

g ac

q u

is it

io n

a n

d g

en er

al iz

at io

n

(D E

C ta

lk ),

w it

h

st u

d y

w it

h s

eq u

en ce

o f

ac q

u is

it io

n f

o r

th re

e se

ts u

si n

g th

re e

d if

fe r-

a Q

W E

R T

Y

ch il d

re n

b ei

n g:

P R

IN T

, S

P E

E C

H -P

R IN

T

en t,

b u

t eq

u iv

al en

t ‘c

al cu

la to

r’ t

yp e

an d

S P

E E

C H

. F

o r

th e

fo u

rt h

c h

il d

t h

e fo

u r-

w o rd

s et

s)

ke yb

o ar

d

se q

u en

ce w

as S

P E

E C

H -P

R IN

T ,

S P

E E

C H

an

d P

R IN

T

S ch

lo ss

er

et

al .

T o c

o m

p ar

e th

e ef

fe ct

iv en

es s

an d

e ff

ic ie

n cy

o f

1 g

ir l

an d

4 b

o ys

, T

h e

V an

ta ge

; T

h e

re su

lt s

in d

ic at

ed f

re q

u en

t re

q u

es ti

n g

u n

d er

C

o n

cl u

si ve

: A

d ap

te d

a lt

er -

[3 8 ]

re q

u es

ti n

g w

h en

p ro

vi d

ed w

it h

s p

ee ch

o u

tp u

t w

it h

a u

ti sm

sy

n th

et ic

b

o th

c o n

d it

io n

s. T

w o p

ar ti

ci p

an ts

r eq

u es

te d

n

at in

g tr

ea tm

en ts

d

u ri

n g

in st

ru ct

io n

( S

P E

E C

H c

o n

d it

io n

) o r

(8 –1

0 y

ea rs

) (D

E C

T al

k)

m o re

e ff

ec ti

ve ly

u n

d er

t h

e S

P E

E C

H c

o n

d i-

d es

ig n

, re

p li ca

te d

a cr

o ss

n

o s

p ee

ch o

u tp

u t

(N O

-S P

E E

C H

c o n

d it

io n

);

ti o n

a n

d o

n e

p ar

ti ci

p an

t re

q u

es te

d m

o re

fi

ve p

ar ti

ci p

an ts

as w

el l

as t

o m

o n

it o r

ch an

ge s

in n

at u

ra l

ef fe

ct iv

el y

u n

d er

t h

e N

O -S

P E

E C

H c

o n

d i-

sp ee

ch p

ro d

u ct

io n

ti

o n

, w

h il e

th er

e w

as n

o d

if fe

re n

ce f

o r

th e

re m

ai n

in g

tw o s

tu d

en ts

. A

s n

o n

e o f

th e

st u

d en

ts r

ea ch

ed c

ri te

ri o n

i t

w as

n o t

p o ss

ib le

to

a ss

es s

ef fi

ci en

cy o

f co

n d

it io

n s.

O n

ly o

n e

st u

d en

t sh

o w

ed a

n i

m p

ro ve

m en

t in

e li ci

te d

vo

ca li za

ti o n

s S

ig af

o o s

et

al .

T o d

et er

m in

e w

h et

h er

S G

D u

se c

o u

ld b

e ta

u gh

t 1 b

o y,

w it

h

B IG

m ac

k; d

ig it

iz ed

W

it h

t h

e o n

se t

o f

in te

rv en

ti o n

t h

e p

er ce

n ta

ge o

f C

o n

cl u

si ve

: [4

8 ]

d ir

ec tl

y as

a r

ep ai

r st

ra te

gy f

o r

co m

m u

n ic

a- P

D D

-N O

S

co rr

ec t

co m

m u

n ic

at io

n r

ep ai

rs i

n cr

ea se

d a

n d

M

u lt

ip le

-b as

el in

e d

es ig

n

ti o n

b re

ak d

o w

n s,

d is

ti n

ct f

ro m

t ea

ch in

g th

e (1

6 y

ea rs

) st

ab il iz

ed a

t 8 0 –1

0 0 %

. A

s S

G D

u se

w as

ac

ro ss

p ar

ti ci

p an

ts in

it ia

ti o n

o f

a re

q u

es t

ac q

u ir

ed a

s a

re p

ai r

st ra

te gy

, d

ev ic

e u

se

ge n

er al

iz ed

t o i

n it

ia te

r eq

u es

ts w

h er

e th

er e

h ad

b ee

n n

o b

re ak

d o w

n i

n c

o m

m u

n ic

at io

n S

ig af

o o s

et

al .

F o ll o w

in g

ac q

u is

it io

n o

f S

G D

t o r

eq u

es t

it em

s T

w o b

o ys

, w

it h

B

IG m

ac k

sw it

ch ;

F o ll o w

in g

ra p

id a

cq u

is it

io n

o f

S G

D u

se s

im il ar

C

o n

cl u

si ve

: [4

5 ]

th e

ai m

o f

th e

st u

d y

w as

t o e

va lu

at e

ra te

s o f

se ve

re a

u ti

sm

d ig

it iz

ed

ra te

s o f

S G

D u

se w

er e

o b

se rv

ed d

u ri

n g

th e

M u

lt ip

le -b

as el

in e

d es

ig n

re

q u

es ti

n g

an d

v o ca

li za

ti o n

s co

m p

ar ed

a cr