The small number of studies included in the present study limited the ability to make inferences when comparing the three models and investigating the strengths and weaknesses of each type of intervention with respect to important outcomes .
Since the outcome of ' reciprocity of social interaction towards others ' could be a dependent variable that might be context -bound to interactions with the child 's parent , we can not conclude the interventions for pre-school children with ASD have significant effects on a generalized skill to engage in reciprocal interactions with others .
However , the outcomes of ' reciprocity of social interaction towards others ' and ' parental synchrony ' may be promising targets for interventions involving pre-school children with ASD .
BACKGROUND There has an increasing number of published trials on psychosocial intervention programmes for pre-school children with autism spectrum disorder ( ASD ) .
To achieve better quality of unbiased evidence for the effectiveness of ASD interventions , it is necessary to conduct a comprehensive review that covers studies with adequate quality st and ards , such as r and omised controlled trials ( RCTs ) , and different types of intervention In this study , we categorize interventions for ASD as behavioural , social-communication focused , and multimodal developmental based on Howlin 's classification of early interventions for children with ASD .
The aim of this study was to compare these three models and investigate the strengths and weaknesses of each type of intervention and to identify the approaches that contribute to a successful outcome for children with autism .
A randomized controlled trial of Hanen's 'More Than Words' in toddlers with early autism symptoms.
BACKGROUND This r and omized controlled trial compared Hanen 's ' More than Words ' ( HMTW ) , a parent-implemented intervention , to a ' business as usual ' control group . METHODS Sixty-two children ( 51 boys and 11 girls ; M age = 20 months ; SD = 2.6 ) who met criteria for autism spectrum disorders ( ASD ) and their parents participated in the study . The HMTW intervention was provided over 3.5 months . There were three measurement periods : prior to r and omization ( Time 1 ) and at 5 and 9 months post enrollment ( Times 2 and 3 ) . Children 's communication and parental responsivity were measured at each time point . Children 's object interest , a putative moderator , was measured at Time 1 . RESULTS There were no main effects of the HMTW intervention on either parental responsivity or children 's communication . However , the effects on residualized gains in parental responsivity from Time 1 to both Times 2 and 3 yielded noteworthy effect sizes ( Glass 's Δ = .71 , .50 respectively ) . In contrast , there were treatment effects on child communication gains to Time 3 that were moderated by children 's Time 1 object interest . Children with lower levels of Time 1 object interest exhibited facilitated growth in communication ; children with higher levels of object interest exhibited growth attenuation . CONCLUSIONS The HMTW intervention showed differential effects on child communication depending on a baseline child factor . HMTW facilitated communication in children with lower levels of Time 1 object interest . Parents of children who evidence higher object interest  may require greater support to implement the HMTW strategies , or may require different strategies than those provided by the HMTW curriculum
The small number of studies included in the present study limited the ability to make inferences when comparing the three models and investigating the strengths and weaknesses of each type of intervention with respect to important outcomes .
Since the outcome of ' reciprocity of social interaction towards others ' could be a dependent variable that might be context -bound to interactions with the child 's parent , we can not conclude the interventions for pre-school children with ASD have significant effects on a generalized skill to engage in reciprocal interactions with others .
However , the outcomes of ' reciprocity of social interaction towards others ' and ' parental synchrony ' may be promising targets for interventions involving pre-school children with ASD .
BACKGROUND There has an increasing number of published trials on psychosocial intervention programmes for pre-school children with autism spectrum disorder ( ASD ) .
To achieve better quality of unbiased evidence for the effectiveness of ASD interventions , it is necessary to conduct a comprehensive review that covers studies with adequate quality st and ards , such as r and omised controlled trials ( RCTs ) , and different types of intervention In this study , we categorize interventions for ASD as behavioural , social-communication focused , and multimodal developmental based on Howlin 's classification of early interventions for children with ASD .
The aim of this study was to compare these three models and investigate the strengths and weaknesses of each type of intervention and to identify the approaches that contribute to a successful outcome for children with autism .