APPENDIX A (Continued).

Summary of main themes, sub-themes and study outcomes relating to communication and language characteristics of young children with VI.

Main themes	Article	Sub-themes	Study outcomes
ASD and multiple disabilities	Absoud et al., 2011	Pragmatic skills Congenital VI Lack of assessment tool Early intervention	There is a lack of ASD and early social communication assessments tools for children with VI.
			A high rate of children with VI present with social communication difficulties and ASD, but there is no test to confirm this.
			The development of the Visual Impairment and Social Communication Schedule (VISS) can assist in early ASD diagnosis for children with VI and subsequent appropriate early intervention.
	Parr et al., 2010	Language abilities Pragmatic skills Congenital VI Stereotyped behaviour	31% of the sample received an ASD diagnosis. Significant cognitive impairment in children with ONH and SOD show a greater risk for ASD. Slightly more children with SOD where diagnosed with ASD than children with ONH. Children with PVI were more likely to present with at least one SCRR difficulty and to show all three SCRR difficulties than children with SVI, but were only slightly more likely to receive an ASD diagnosis. VI with ASD resulted in significantly lower verbal comprehension and expressive language structure. ASD was typically diagnosed in children with ONH or SOD, usually between 2.4 to 4.6 years. No evidence that additional neuro-anatomical abnormalities, other than those associated with ONH and SOD, further increased the risk of ASD
	Hoevenaars-van den Boom	Language abilities Pragmatics skills Congenital VI Stereotyped behaviour Lack of assessment tool Cognitive impairment Differential diagnosis	It is difficult to distinguish ASD from deafblindness behaviours, especially in the presence of intellectual disability, and this can lead to overdiagnosis and incorrect intervention. The presence of congenital deafblindness showed an increased risk ASD. Communication and language development were primarily affected by congenital deafblindness, although other developmental areas were likely to be impacted. People with deafblindness often remain at a prelingual communication level and may never reach a symbolic communication level, especially in the presence of intellectual disability. Children with deafblindness demonstrated shared attention, but learning and using nonverbal behaviour was compromised by VI.
			Children with deafblindness missed auditory and visual communicative signals, unlike in ASD where signals were not understood.
			The existing standardised tests, questionnaires and developmental scales for ASD are not reliable or valid for people with deafblindness because the accumulated effect of multiple disabilities is not considered. Children with congenital deafblindness had similar characteristics to the ASD triad of impairment. Children with ASD, intellectual disability and deafblindness had significantly more difficulty than children with intellectual disabilities and deafblindness but no ASD in terms of: - openness for contact - joint attention - communication functions. Children with ASD, intellectual disabilities and deafblindness had almost statistically significantly more difficulty than children with intellectual disabilities and deafblindness but no ASD in terms of: - coping with changes - problem solving strategies. Children with ASD, intellectual disabilities and deafblindness did not have significantly more difficulty than children with intellectual disabilities and deafblindness but no ASD in terms of: - stereotyped behaviour - exploration and play. The stereotyped behaviours demonstrated by children with deafblindness decreased with increased: - age - interaction initiation and maintenance - opportunity to communicate. Both children with ASD, intellectual disabilities and deafblindness, and children with intellectual disabilities and deafblindness but no ASD demonstrate: - limited functional play as this may have been linked to intellectual disabilities - increased object manipulation Children with ASD, intellectual disabilities and deafblindness had more ASD-specific behaviours than children with intellectual disabilities and deafblindness but no ASD.
			The results can assist with differentiation during diagnosis.
	Peltokorpi & Huttunen, 2008	Language abilities Communication abilities Pragmatic skills Congenital VI	Children with CHARGE demonstrated ASD-like traits, but their language and communication was better than children with ASD.
			Limited eye contact may be due to VI or ASD-like behaviour.

ASD, Autism Spectrum Disorder; VI, visual impairment; OHN, optic nerve hypoplasia; SOD, septo-optic dysplasia; SCRR, social, communication and/or restrictive or repetitive behaviour; PVI, profound visual impairment; SVI, severe visual impairment.