Studies of any design of social and communicative interventions in youths aged 12 to 22 years with disabilities eligible for inclusion in the review if they had a measured outcome and sufficient data with which to calculate an effect size.
Non-randomised studies in which it was unclear whether groups were comparable were excluded from the review.
Interventions included: augmentative and alternative communication (AAC), which included vocalisations, movements or micro-switch activation and use of symbols; conversation skills; decreasing inappropriate behaviour; and social skills training (SST). Duration and intensity of the same type of intervention varied widely between studies. Outcomes were transition or transition-related outcomes and included improvement in conversation and related social/communicative skills, and reduction in disruptive behaviour. Participants' mean age ranged from 13 to 21 years. Disabilities included: mild, moderate, severe and profound cognitive disabilities; autism and autism spectrum disorder; severe cognitive disabilities with a range of vision and hearing impairment; Down's syndrome; cerebral palsy; emotional/behavioural disorders; and multiple disabilities. Settings included residential facilities, state institutions, 24-hour group homes, special education school environments, comprehensive school environments, vocational training sites and job sites. Study designs included between-group (pre-test and/or post-test), within groups (crossover design) and single participant design.
The authors reported on the various stages of study selection, which included dual coding and consensus process. For the selection of the final set of studies the authors stated that all staff used an inductive process to sort the studies by intervention constructs, which identified studies that conformed to the authors' definitions of social and communicative interventions.