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 .
Randomized comparative efficacy study of parent-mediated interventions for toddlers with autism.
OBJECTIVE This study compared effects of two parent-mediated interventions on joint engagement outcomes as augmentations of an early intervention program for toddlers with autism spectrum disorder ( ASD ) . METHOD Participants included 86 toddlers ( range 22 - 36 months ) with ASD and their primary caregiver . Caregiver-child dyads were r and omized to receive 10 weeks of h and s-on parent training in a naturalistic , developmental behavioral intervention ( joint attention , symbolic play , engagement and regulation-JASPER ) or a parent-only psychoeducational intervention ( PEI ) . Dose was controlled in terms of research er-parent contact and early intervention services received by the child . RESULTS Results yielded significant effects of the JASPER intervention on the primary outcome of joint engagement . The treatment effect was large ( Cohen 's f² = .69 ) and maintained over the 6-month follow-up . JASPER effects were also found on secondary outcomes of play diversity , highest play level achieved , and generalization to the child 's classroom for child-initiated joint engagement . The PEI intervention was found to be effective in reducing parenting stress associated with child characteristics . All secondary effects were generally small to moderate . CONCLUSIONS These data highlight the benefit of a brief , targeted , parent-mediated intervention on child outcomes . Future studies may consider the combination of JASPER and PEI treatments for optimal parent and child outcomes . Trial registry no. NCT00999778
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 .