There was no evidence that AAC improved frequency of speech , verbal expressive vocabulary or children 's social communication or pragmatic language immediately postintervention .
Overall , neither of the interventions ( PECS or FPI ) result ed in maintained improvements in spoken or non-verbal communication in most children .
AUTHORS ' CONCLUSIONS There is limited evidence that verbally based and ACC interventions improve spoken and non-verbal communication in minimally verbal children with ASD .
In the study that used an AAC intervention , there were significant gains in frequency of PECS use and verbal and non-verbal initiations , but not in expressive vocabulary or social communication immediately postintervention .
In the study that investigated a verbally based intervention , there were no significant gains in expressive language postintervention , but children with lower expressive language at the beginning of the study improved more than those with better expressive language at baseline .
Neither study investigated adverse events , other communication skills , quality of life or behavioural outcomes .
BACKGROUND Autism spectrum disorder ( ASD ) has an estimated prevalence of around 1.7 % of the population .
People with ASD often also have language difficulties , and about 25 % to 30 % of children with ASD either fail to develop functional language or are minimally verbal .
The ability to communicate effectively is an essential life skill , and difficulties with communication can have a range of adverse outcomes , including poorer academic achievement , behavioural difficulties and reduced quality of life .
Historically , most studies have investigated communication interventions for ASD in verbal children .
We can not assume the same interventions will work for minimally verbal children with ASD .
OBJECTIVES To assess the effects of communication interventions  for ASD in minimally verbal children .
A communication-based intervention for nonverbal children with autism: what changes? Who benefits?
OBJECTIVE This article examines the form and function of spontaneous communication and outcome predictors in nonverbal children with autism following classroom-based intervention ( Picture Exchange Communication System [ PECS ] training ) . METHOD 84 children from 15 schools participated in a r and omized controlled trial ( RCT ) of PECS ( P. Howlin , R. K. Gordon , G. Pasco , A. Wade , & T. Charman , 2007 ) . They were aged 4 - 10 years ( 73 boys ) . Primary outcome measure was naturalistic observation of communication in the classroom . Multilevel Poisson regression was used to test for intervention effects and outcome predictors . RESULTS Spontaneous communication using picture cards , speech , or both increased significantly following training ( rate ratio [ RR ] = 1.90 , 95 % CI [ 1.46 , 2.48 ] , p < .001 ; RR = 1.77 , 95 % CI [ 1.35 , 2.32 ] , p < .001 ; RR = 3.74 , 95 % CI [ 2.19 , 6.37 ] , p < .001 , respectively ) . Spontaneous communication to request objects significantly increased ( RR = 2.17 , 95 % CI [ 1.75 , 2.68 ] , p < .001 ) , but spontaneous requesting for social purpose s did not ( RR = 1.34 , 95 % CI [ 0.83 , 2.18 ] , p = .237 ) . Only the effect on spontaneous speech persisted by follow-up ( 9 months later ) . Less severe baseline autism symptomatology ( lower Autism Diagnosis Observation Schedule [ ADOS ] score ; C. Lord et al. , 2000 ) was associated with greater increase in spontaneous speech ( RR = 0.90 , 95 % CI [ 0.83 , 0.98 ] , p = .011 ) and less severe baseline expressive language impairment ( lower ADOS item A1 score ) , with larger increases in spontaneous use of speech and pictures together ( RR = 0.62 , 95 % CI [ 0.44 , 0.88 ] , p = .008 ) . CONCLUSION Overall , PECS appeared to enhance children 's spontaneous communication for instrumental requesting using pictures , speech , or a combination of both . Some effects of training were moderated by baseline factors . For example , PECS appears to have increased spontaneous speech in children who could talk a little at baseline
There was no evidence that AAC improved frequency of speech , verbal expressive vocabulary or children 's social communication or pragmatic language immediately postintervention .
Overall , neither of the interventions ( PECS or FPI ) result ed in maintained improvements in spoken or non-verbal communication in most children .
AUTHORS ' CONCLUSIONS There is limited evidence that verbally based and ACC interventions improve spoken and non-verbal communication in minimally verbal children with ASD .
In the study that used an AAC intervention , there were significant gains in frequency of PECS use and verbal and non-verbal initiations , but not in expressive vocabulary or social communication immediately postintervention .
In the study that investigated a verbally based intervention , there were no significant gains in expressive language postintervention , but children with lower expressive language at the beginning of the study improved more than those with better expressive language at baseline .
Neither study investigated adverse events , other communication skills , quality of life or behavioural outcomes .
BACKGROUND Autism spectrum disorder ( ASD ) has an estimated prevalence of around 1.7 % of the population .
People with ASD often also have language difficulties , and about 25 % to 30 % of children with ASD either fail to develop functional language or are minimally verbal .
The ability to communicate effectively is an essential life skill , and difficulties with communication can have a range of adverse outcomes , including poorer academic achievement , behavioural difficulties and reduced quality of life .
Historically , most studies have investigated communication interventions for ASD in verbal children .
We can not assume the same interventions will work for minimally verbal children with ASD .
OBJECTIVES To assess the effects of communication interventions  for ASD in minimally verbal children .