Postępy Nauk Medycznych, t. XXVI, nr 1, 2013

WYTYCZNE KLINICZNE

CLINICAL CORNER©BorgisMonika Suchowierska1, Monika Rupińska1, Andy Bondy2

Picture Exchange Communication System (PECS):
A Short “tutorial” for the doctors
Picture Exchange Communication System (PECS):„Przewodnik” dla lekarzy
Department of Psychology, University of Social Sciences and Humanities, Warszawa, Poland
Head of Department: Ewa Trzebińska, PhD
2
Pyramid Educational Consultants, Inc.
Chairman of PEC, Inc.: Andy Bondy, PhD
1

Summary
One area of persistent difficulties for children with autism is communication, with about 25% of individuals with autism notdeveloping spoken language at all. In light of this information, it is of paramount importance to have means of teaching thoseindividuals how to pass to others information about their needs and wants in a socially appropriate and easily understoodmanner. Picture Exchange Communication System (PECS) is an empirically-validated alternative and augmentative communication method. In the present article we will provide a brief tutorial on PECS that may be of help to health care professionals
who in their work come across children with autism.
Key words: autism, PECS, pictorial communication, language development
StreszczenieJedną ze sfer, która jest zaburzona u osób z diagnozą autyzmu jest komunikacja. Około 25% osób z autyzmem nie rozwija
mowy jako sposobu komunikowania się. Jest zatem bardzo ważną kwestią, aby klinicyści mieli do dyspozycji metody nauczania osób z autyzmem przekazywania informacji w inny sposób niż słowami. Picture Exchange Communication System(PECS) jest opartą na dowodach i wywodzącą się z psychologii behawioralnej techniką uczenia porozumiewania się osób
z autyzmem. W obecnym artykule przedstawimy krótki „przewodnik” po PECS. Mamy nadzieję, że będzie on przydatny dlalekarzy, którzy mogą mieć do czynienia z dziećmi z autyzmem. Założeniem jest przekazanie lekarzom wiedzy potrzebnej dodawania rekomendacji rodzicom odnośnie udowodnionych naukowo metod terapeutycznych dla dzieci z autyzmem.
Słowa kluczowe: autyzm, PECS, komunikacja obrazkowa, rozwój mowy

INTRODUCTION
In 2009 Golnik et al. (1) conducted a study to explore the perspective of general pediatricians and family physicians on primary care for children with autism
in the USA. Results of this research revealed that doctors rated themselves much less competent and lesseducated in the area of developmental disabilities
than in case of other childhood neurodevelopmental
conditions. This is a concern taking into account that,
according to Dosreis et al. (2), the majority of general
pediatric providers have had contact with children with
autism. Additionally, studies show that children with
autism use health care services more often than typically developing children, presumably due to medical
conditions that co-occur with autism as well as be-

havioral and emotional problems (3). Respondents in
Golnik et al.’s study expressed a great desire for autism education, both from the perspective of improving
knowledge base and as a likely means of increasing
competency in daily practice. Such results are in linewith the fact that primary health care providers differ in
how much they know about autism, especially aboutprognosis, course and treatment when compared toprofessionals working directly with this population (4).
Thus, it is of paramount importance to pass informationfrom the clinicians and scientist-practitioners to medical doctors, so that a more comprehensive support forchildren with complex health care needs is provided.
One area of persistent difficulties for children with
autism is communication (5). Not only is the develop85

Monika Suchowierska, Monika Rupińska, Andy Bondy
ment of language delayed, but approximately 25% ofchildren with autism do not develop functional speech(6). That means that if they are not taught alternative
to speech ways of conveying their needs, wants andobservations, they are virtually not able to pass various messages to others in a socially acceptable ways.
A likely result of this is development of inappropriate
behaviors that serve a communicative function (7).
Applied behavior analysis (ABA) is a discipline thatprovided foundation for many effective techniques ofteaching numerous skills to children with autism (8).
Behavioral strategies have been successfully used toteach language to atypically developing children, boththose who can speak and those for whom speaking isvery difficult or impossible (9). For the latter group of
pupils, one communication strategy that has its rootsin ABA is Picture Exchange Communication System(PECS). Because of the popularity of PECS in clinicaland school settings and its empirical basis (10), we
believe it is important that primary health care providers are aware of this strategy, so they can make recommendations to parents, if needed. In the following
paragraphs, we will provide a short “tutorial” on thecharacteristics and effectiveness of PECS. We also will
briefly discuss some of the misconceptions associatedwith PECS.
Picture Exchange Communication System (PECS)
was developed by Dr. Andy Bondy and Lori Frost as amethod of teaching induviduals with autism and otherdevelopmental dlisabilities how to engage in functional
communication. It is usually, although not necessarily,a picture-based system that may serve as an alternative or augmentative communication. PECS is strongly
based on basic principles of behavior, especially positive reinforcement and shaping of new responses, andit has its origin in B.F. Skinner’s analysis of verbal behavior (11). The main focus of PECS is to teach spontaneous, functional social-communication skills (12).
According to Skinner (11), verbal behavior is learned
behavior mediated through the action of others, whichmeans that the reinforcement is dependent on the whatsomeone else does. For example, if a child is thirsty,
he can get a drink on his own (this would not be an
instance of verbal behavior since the child’s behavior
was reinforced via a straightforward change in the environment) or he/she can get someone else to give him
a drink by asking for it (this would be an instance of
verbal behavior because reinforcement, i.e., the drink,
was facilitated by another person). Frost and Bondy(13) write that “communication involves behavior (defined in form by the community) directed to anotherperson who in turn provides direct or social rewards”(pg. 24). This definition can be treated as analogous tosaying that functional communication is the exchange
of information between at least two people. The message may be delivered using words, gestures, texts,
images or symbols. Therefore, communication can bedivided into vocal (words, vocalizations) and non-vocal
communication (gestures, facial expressions, pictures,
86

symbols). However, communication is not mere gestures or words. In order to talk about “communication”,
certain conditions must be met:
– at least two people participate (“the speaker” and“the listener”),– one person (“the speaker”) has to address thesecond person,– “the listener” responds to the message comingfrom the “speaker” in ways that have been conditioned precisely so that the behavior of the speaker is reinforced.
In other words, functional communication is a kindof an “exchange” of information between the speaker
and the listener. The listener reacts appropriately to theactivity of the speaker by providing reinforcement (e.g.
giving attention or a desired item). As already mentioned, the communication does not have to be doneby means of words. For example, pictures/gestures//written words can be used. In PECS, as the namesuggests, pictures are used most often. What is mostimportant, though, is that the transmission of information is understood by the people participating in theexchange of information.
PECS is not only the name of a system used bychildren with autism. It is also a well-designed protocol for teaching communication to pupils who havelanguage delays (13). The PECS teaching protocol isbased on B.F. Skinner’s approach to understanding
verbal behavior. Verbal behavior – or communication– is subject to basic principles of behavior and can betaught using behavioral techniques – reinforcement,
prompting, shaping. A proper implementation of the
PECS teaching protocol should ultimately lead to independent communication of the people who previously
had difficulty with such an activity. The PECS teaching
protocol consists of six phases which should be taught
sequentially. Each phase should be mastered before
teaching the next one is begun.
PECS PHASES
Phase I (Physical Exchange) teaches a child how
to communicate. The student learns that if he wants
something but does not have access to it, he needs
to hand a picture to a communicative partner. It is important to remember that communication is about theexchange between two people – “the speaker” givesa picture to “the listener” and the listener, having understood the message, gives the desired item to thechild. During this phase one should not ask the student
directly about what he wants (e.g., “what do you want”,“do you want it?” etc.). The student himself will show
us what he wants at any given time (e.g. by reachingout for something). In the first phase, it is not crucial
that there is actually a correct drawing on the pieceof paper. As a matter of fact, the drawing is less of an
essence than the exchange itself. In this phase, we
do not teach discrimination (i.e., choosing) of one oftwo pictures, either. The students has only one picture
available at a time. The first phase is mastered when

Picture Exchange Communication System (PECS): A Short “tutorial” for the doctors
the student by himself (without any suggestions) picks
up a picture of the item, reaches toward the trainer, andreleases the picture into the trainer’s hand.
Phase II (Expanding Spontaneity) teaches the “triangle of communication” (i.e., me, my communication
book, and my communicative partner). The student stilluses individual pictures but at this stage he learns how
to generalize the new skill. Generalization is ability to
exchange information with a variety of communicative
partners (e.g., mom, dad, grandma), in many different
settings (e.g., preschool, kitchen, playground) and under diverse conditions (e.g. the listener is standing far
away, the listener is turned away from the child). At thisstage, we teach persistence in communication! We still
do not teach discrimination. Phase II is mastered when
the student is able to find his own communication bookand the communication partner to whom he must pass
the picture.
Phase III (Picture Discrimination) teaches selecting the correct image from many possibilities. The
student learns how to make a choice between two or
more images to get the item that he really wants toget. Pictures can be found in the communication book(in the form of a binder) and they are attached witha Velcro tape, thus being readily available at the timeof communication. First, we teach how to discriminate
between highly desired items and the undesired ones,
later the desired versus neutral and at the end we proceed to the two desired objects. During the exchange,
one should remember about naming the items as wegive them to the student after the communication takes
place. Furthermore, in this phase we begin to teach themeaning of the words “wait” and “no”. We can move tothe next phase only if the student chooses the item that
corresponds to his desires at the time. In addition, thestudent should look into the book to find the picture.
Phase IV (Sentence Structure) teaches the student to “utter” longer requests. The student learns toconstruct simple sentences by means of a sentence
strip, using the picture “I want,” and then an image ofthe object that he asks for. The student gives his sentence strip to the communication partner who reads
the sentence “I want...”, waits maximum 5 seconds fora verbal reaction and then adds the name of the item,
such as, for instance, “a car”. In this way, the childis encouraged to speak. One should augment thesuccessful vocal attempts. We can move to the next
phase only when the students learns how to make his
own sentence strip. When the skill is mastered, the student often moves to phase V and learns how to makeelaborate sentences by adding adjectives, verbs andprepositions.
Phase V (Responding to “What do you want?”)
teaches how to respond to questions. The student
learns to use PECS in order to answer the following
question: “What do you want?”. One should alternate
between spontaneous opportunities to ask and to reply
to the question “What do you want?”. We can moveto the next phase only if the student responds to thequestion “What do you want?” and spontaneously
makes requests by himself.
Phase VI (Responsive and Spontaneous Commenting) teaches commenting on what happens in thesurrounding environment. The student learns how tocomment and respond to such questions as: “What doyou see?”, “What do you hear?”, “What do you feel?”,“What is it?”. He learns to make sentences with “I cansee...”, “I can hear...”, “I can feel...”, “This is...” etc.
At the end of this phase, the student should ask questions spontaneously, answer them using the vocabulary and primer in a sentence as well as comment on
the surrounding environment. One must remember tocheck the student’s skills regularly and create situations in which he may use them. During the PECS implementation one has to teach the student how react tothe word “no” correctly.
Since mid 1990s when PECS was developed, there
have been about 60 studies looking at various aspectsof the system. As for parents of children with autism andprofessionals who may come across those parents, it
is very important to know how effective is PECS. Below
we will present the results of three recent reviews (metaanalyses) of single subject studies devoted to PECS:– Hart and Banda 2010 (14)– Preston and Carter 2009 (15)
– Flippin, Reszka and Watson 2010 (16)We chose those studies, as in the last 30 years metaanalysis has been accepted in the social and health sciences as a very useful and helpful research methodology to quantitatively integrate the results from different
studies (17, 18). The most commonly used statistical index for single-subject designs is the percentage of nonoverlapping data (PND) (16, 17). The PND is the percentage of intervention data points that are above (whenbehavior increase is expected) or below (when behavior
decrease is expected) the highest (or lowest) baseline
data point. If a study includes several experiments, PND
scores are aggregated by taking the median.
Interpretation of PND as described by Scruggs andMastropieri (19) is as follows: scores between 91 and100 indicate highly effective interventions, between 71
and 90 moderately effective interventions, between 51
and 70 questionably effective interventions, and 51 or
below ineffective intervention.
Based on the three above-mentioned studies, wewill describe the effects of using PECS on overall communication skills, on speech development and on levels of problem behavior.
Overall communication abilities. The overall effectiveness of PECS training was indicated in termsof increases in communication exchanges, speech,
and social behavior as well as decreases in problem
behavior. Two meta-analyses included the measureof overall effectiveness (14, 15). Hart and Banda (14)meta-analysis presented the following results: the intervention was highly effective for 19 of 35 participants,
moderately effective for 10 participants, minimally effective for 5 participants and showed no effect for87

Monika Suchowierska, Monika Rupińska, Andy Bondy
1 participant. In terms of overall effectiveness, PECS
training was effective (highly and moderately) for 83%
participants. Second meta-analysis was computed by
Preston and Carter (15). According to its results, PECS
training was highly effective for four of ten studies,moderately effective for two studies and questionably
effective for four studies. In this meta-analysis authors
calculated overall mean PND for all studies and it was
78.5% (moderately effective). In sum, PECS training
was an effective intervention to increase overall communication abilities (exchange picture, speech, social
behavior – e.g. pointing) for children with autism.
Picture exchange (augmentative and alternative
communication). Communication outcomes included
frequency of use of PECS, exchanges, requests and initiations. Preston and Carter (15) meta-analysis presented the following results: in terms of picture exchange,
PECS training was a highly effective intervention for sixof nine studies, moderately effective for two of nine studies, and questionably effective for one of nine studies.
The overall mean PND for picture exchange was 90%(between moderately and highly effective). Very similar
overall mean PND for picture exchange obtained Flippin, Reszka and Watson (16), and it was 84.3% (moderately effective). In this meta-analysis for the following measures – picture exchange, PECS training wasa highly effective intervention for three of five studies
and a questionably effective application for one study.
In sum, PECS was shown to be an effective intervention
to increase functional communication, which is augmentative and/or alternative to speech.
PECS versus other interventions. Hart and Banda (14) described a comparison of PECS with a sign
language intervention and PECS with VOCA (Voice
Output Communication Aid). PECS was highly effective for 5 of 6 participants and moderately effective for
1 participant. Sign language was highly effective for 2of 6 participants, moderately effective for 1 participant,questionably effective for 2 participants and showedno effect for 1 participant. In sum, PECS appears to bea more effective intervention than sign language to increase functioning communication. However, the nextcomparison, i.e. PECS to VOCA, showed different results. PECS was highly effective for 3 of 9 participants,
moderately effective for 4 participants and questionably
effective for 2 participants. VOCA was highly effective
for 2 of 9 participants, moderately effective for 5 participants and questionably effective for 2 participants.
Thus, PECS and VOCA appear to be equally effective
interventions to increase functional communication.
Speech development. All three meta-analyses included results for speech development. Hart and Banda (14) meta-analysis presented the following results
for speech gains: PECS training was highly effective
for 2 of 10 participants, moderately effective for 2 participants, questionably effective for 2 participants, andshowed no effect for 1 participant. PND for 3 participants could not be calculated for speech because of
unclear data. These results suggested that for some88

children PECS training may be an effective intervention
to increase speech (vocal communication). Preston
and Carter (15) meta-analysis showed less optimistic
results for speech gains. For speech development,
PECS training was highly effective for one of four studies, questionably effective for one study and showed noeffect for 2 studies. The overall mean PND for speech
development was 49.8% (questionably effective). Flippin et al. (16) meta-analysis showed similar results.
For speech development, PECS training was highly effective for one of four studies, questionably effective
for one study and showed no effect for 2 studies. The
overall mean PND for speech development was 44.7%(questionably effective). Researchers found a relationship between speech development and phases during
PECS training (14-16). Usually spontaneous and imitative speech increased during the later phases of PECS
(IV to VI). Phase IV introduces sentence structure andtime delay strategies. The trainer says “I want…” andbriefly pauses (4-5 sec.) before giving the requested
object to the child and finishing the sentence. Thus,time delay serves as an establishing operation for
naming the desired item. It is important to remember,though, it is not only phase IV in which verbal modeling takes place. As a matter of fact, this strategy (i.e.,saying the name of the desired object once the childhands in its icon) is done beginning with phase I.
Reducing problem behavior. In terms of reducing
problem behavior, Hart and Banda (14) showed that
PECS training was a highly effective intervention for
one of four participants, moderately effective for twoparticipants, and questionably effective for one participant. Preston and Carter (15) meta-analysis describedjust two studies for problem behavior. For a reduction ofproblem behavior, PECS training was a highly effective
intervention for one study and moderately effective forother one study. This results suggested that PECS is aneffective intervention for decreasing problem behavior(e.g. tantrums, grabbing, out of seat, throwing objects).
Based on the above mentioned meta-analyses wemay conclude that PECS training has been highly ormoderately effective for many participants (more thanhalf) with autism in increasing functional communication skills. Moreover, some participants that used PECS
increased speech and decreased problem behavior.
On balance, the reviewed studies provide evidence that
PECS training may be an effective intervention for children with autism who have little or no speech. A very
recent publication by Maglione et al. (20) provides
guidelines regarding nonmedical interventions for children with autism. Based on a systematic review of scientific evidence, the authors conclude that research regarding PECS offers moderate strength of evidence ofefficacy (i.e., the experts were reasonably confident of
the intervention’s positive effects). Investigators recommend that “individuals with autism spectrum disorders
who have limited verbal language, or those who do notrespond to multiple interventions aimed at improving
communication, should be offered the opportunity toPicture Exchange Communication System (PECS): A Short “tutorial” for the doctors
use PECS” (pg. 175). In the same article, Maglione et al.
mention that they had not identified any controlled trials
or observational studies on the efficacy or effectivenessof Augmentative and Alternative Communication (AAC)
tools. PECS is well suited to be transitioned to a varietyof AAC, including high-tech speech generating devices(SGDs). Frost and McGowan (21, 22) write about criticalfactors in transitioning from PECS to SGDs. This publication is noteworthy as PECS is often the first intervention implemented for children who do not speak, but
as they progress through PECS phases (usually after
they have mastered Phase IV), parents as well as professionals may want to move to a system which accommodates expanding vocabulary and complexity of communicative interactions. The authors emphasize the factthat in order for the transition from PECS to SGDs to be
successful it must be done so that the individual does
not lose any current communication abilities. Despite
the fact that nowadays we have more information on theeffectiveness of PECS than even five years ago and that
this system is widely used, at least in the US (23), many
common misunderstandings about this therapeutic application are still prevailing. Some of them are listed in
Bondy (24) and summarized below:

place, by introducing a time delay between first part ofthe sentence (i.e., I want) and the name of the desired
object). Thus, teaching that speaking is an ubiquitous
activity is an inherent part of PECS.

If you use visual stimuli, it is PECS
The effectiveness of the PECS training is not basedon a specific kind or number of pictures, but on theassumptions of the whole system and how it is implemented. An important element of this system is to learn
that the functional communication serves as a tool toexchange information (for example, by means of visual
stimuli, but not necessarily). One may use visual stimuli
and not use PECS at all.

Do not take the PECS book away from a child because
by doing so we would remove the tool that the child uses
to communicate with the environment. The child will
reject PECS naturally as soon as he notices that otherpeople understand what he says (vocally). Usually, “shifting” from the PECS book to speech takes place graduallyand is directed by the child. Non-vocal verbal behavior
is slowly replaced by another operant which serves thesame function – vocal verbal behavior.

If you use activity schedules, it is PECS

PECS means giving the child anything he wants

The PECS system is based on “active speech”, theperson “asks” for things he wants or “says” what isof interest to him. The activity schedule, on the other
hand, refers to “passive speech”, as the person “reads//recognizes” what he or she would do.

Only in Phases I and II one should make sure thatthe child has received the item he is asking for. In thesephases, the child is taught that communication has
the power and by means of it he can say anything hewants. In the later phases, the child learns to accept a“no” and the information “wait”.

PECS is developed only for children who do not
speakThis system can be used as an alternative or augmentative communication depending on the child’s
needs. This means that it can be used by children who
do not speak at all as well as the ones who have difficulty speaking. (e.g. indistinct pronunciation). The idea
behind using PECS for children for whom speech is astrenuous activity is to lower the effort needed for communication, thus reinforce verbal behaviour meanwhileworking on clearer or easier production of words.
If you start to use PECS, you stop teaching
how to speak
In PECS, the communicative partner always tries
to promote speech (e.g., via naming pictures that are
given to him by the speaker before an exchange takes

If you start using PECS, the child will haveno motivations to learn how to speak
The development of speech is related to many factors, such as: the age of the child, history of reinforcement for speaking, level of impairment and, thus, may
not depend solely on using or not using PECS. Thus, byintroducing PECS we give a student additional support
to convey a message to the other person. We do nottake away motivation to learn how to speak. Just the
opposite, via providing many models of speaking while
teaching PECS, we model to the children that communication with the aid of the language is faster and has
immediate results as opposed to pictorial communication (you need to find the right picture and give it to theperson). For some children PECS leads to vocalizations
and use of speech and for some others, it does not. The
difference seem to be related to the nature of autism.
As soon as the child begins to speak, we should
quit using PECS

PECS is only for young children with autism
Indeed, the PECS protocol was developed in thelate 1980s for young children with autism. Since then,however, there have been several studies conductedinvestigating the effectiveness of the system for adults
with a variety of communication handicaps. Research
has also been done with children with other disabilities
than autism (e.g., cerebral palsy, blindness, deafness,
multiple disabilities. Certainly more research with varied populations is needed but based on the available
data PECS seems to be a viable communication intervention not only for children with autism.
There is no empirical research devoted to PECS
The overview of literature spanning over the last
15 years (since mid-1990s) shows that there are more
89

Monika Suchowierska, Monika Rupińska, Andy Bondy
than 60 empirical studies, several comprehensive reviews and also a few meta-analyses related to PECS.
Although their results are varied, some of them describing PECS as an established effective intervention,others portraying PECS as a promising method forincreasing communication skills – researchers agree
that the PECS protocol “appears to be associated withimprovements in communication and speech production and with other positive behavior changes” (24, pg.
811).
In conclusion, PECS is a method that has beencreated specifically for individuals who have language

development difficulties. It is based on applied behavior analysis and thus is supported by strong theoretical foundation – mainly Skinner’s analysis of verbal
behaviour – and empirical research. The system itself
has been evaluated in a number of separate studies aswell as few meta-analyses. The overall conclusion isthat PECS is an effective, evidence-based method thatteaches children how to communicate effectively andefficiently. It also reduces rates of problem behavior
and for some children is associated with speech development. For interested individuals, more information
on PECS can be found at: www.pecs.com

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received/otrzymano: 07.11.2012
accepted/zaakceptowano: 17.12.2012

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Address/adres:*Monika Suchowierska
University of Social Sciences and Humanities
ul. Chodakowska 19/31, 03-815 Warszawa
tel.: +48 (22) 517-99-22
e-mail: monika.suchowierska@swps.edu.pl