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 .
Preschool-based social communication treatment for children with autism: 12-month follow-up of a randomized trial.
OBJECTIVE This study reports 12-month follow-up data from a r and omized controlled trial of preschool-based social communication treatment for young children with autism . METHOD A total of 61 children ( 48 males ) with autism , 29 to 60 months of age , had earlier been r and omized either to 8 weeks of preschool-based social communication treatment in addition to st and ard preschool program ( n = 34 ) or to st and ard preschool program only ( n = 27 ) . Significant short-term effects on targeted social communication skills have previously been published . Long-term gains in social communication , language and global social functioning and communication were assessed from video-taped preschool teacher-child and mother-child interactions , Early Social Communication Scales , Reynell Developmental Language Scale , and Social Communication Question naire . RESULTS Compared with those in the control group , the treated children achieved significantly larger improvements in joint attention and joint engagement from baseline to 12-month follow-up . However , no effects were detected on language and global ratings of social functioning and communication . The treatment effect on child initiation of joint attention increased with increasing level of sociability at baseline , whereas nonverbal IQ and expressive language had no moderating effect . CONCLUSIONS This study is the first to show that , similar to specialist-delivered treatment , preschool-based treatment may produce small but possibly clinical ly important long-term changes in social communication in young children with autism . The treatment did not affect language and global ratings of social functioning and communication . More studies are needed to better underst and whether treatment effects may be improved by increasing the intensity and duration of the treatment . Clinical trial registration information -- Joint Attention Intervention and Young Children With Autism ; http:// clinical trials.gov/ ; NCT00378157
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 .