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 .
Longitudinal Effects of Adaptive Interventions With a Speech-Generating Device in Minimally Verbal Children With ASD
There are limited data on the effects of adaptive social communication interventions with a speech-generating device in autism . This study is the first to compare growth in communications outcomes among three adaptive interventions in school-age children with autism spectrum disorder ( ASD ) who are minimally verbal . Sixty-one children , ages 5–8 years , participated in a sequential , multiple-assignment r and omized trial ( SMART ) . All children received a developmental behavioral communication intervention : joint attention , symbolic play , engagement and regulation ( JASP ) with enhanced milieu teaching ( EMT ) . The SMART included three 2-stage , 24-week adaptive interventions with different provisions of a speech-generating device ( SGD ) in the context of JASP+EMT . The first adaptive intervention , with no SGD , initially assigned JASP+EMT alone , then intensified JASP+EMT for slow responders . In the second adaptive intervention , slow responders to JASP+EMT were assigned JASP+EMT+SGD . The third adaptive intervention initially assigned JASP+EMT+SGD ; then intensified JASP+EMT+SGD for slow responders . Analyses examined between-group differences in change in outcomes from baseline to Week 36 . Verbal outcomes included spontaneous communicative utterances and novel words . Nonlinguistic communication outcomes included initiating joint attention and behavior regulation , and play . The adaptive intervention beginning with JASP+EMT+SGD was estimated as superior . There were significant ( p < .05 ) between-group differences in change in spontaneous communicative utterances and initiating joint attention .  School-age children with ASD who are minimally verbal make significant gains in communication outcomes with an adaptive intervention beginning with JASP+EMT+SGD . Future research should explore mediators and moderators of the adaptive intervention effects and second-stage intervention options that further capitalize on early gains in treatment
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 .