Assessing early communication skills at 12 months: a retrospective study of Autism Spectrum Disorder.

BACKGROUND: Early identification of Autism Spectrum Disorder (ASD) is currently limited by the absence of reliable biological markers for the disorder, as well as the reliability of screening and assessment tools for children aged between 6 and 18 months. Ongoing research has demonstrated the importance of early social communication skills in differentiating children later diagnosed with ASD from their typically developing (TD) peers, but researchers have not yet investigated whether these differences can be detected using community-ascertained systematic observation data as early as 12 months. AIMS: To investigate whether differences in early social communication skills can be detected at 12 months of age, comparing children later diagnosed with ASD, and TD peers; and to determine whether differences remain when groupings are based on age of subsequent ASD diagnosis. METHODS & PROCEDURES: From a prospective community-ascertained sample, we collected data on children in early life, then conducted retrospective analyses for those children who were later diagnosed with ASD by the age of 7 years, compared with matched TD peers. We analysed standardized observational data of early communication skills, collected using the Communication and Symbolic Behavior Scales-Developmental Profile (CSBS-DP) Behavior Sample, when participants were 12 months of age. OUTCOMES & RESULTS: Children in the ASD group exhibited significantly lower social communication skills than the TD group, including on the Total score and Social and Symbolic Composite scores of the CSBS-DP Behavior Sample. Differences on the Total score and Social Composite were also detected for both early and late ASD diagnosis groups when compared with the TD group. CONCLUSIONS & IMPLICATIONS: These findings give further support for the importance of social communication in assessing children at risk of ASD as early as 12 months of age. Future research could evaluate the sensitivity and specificity of direct observation of these early communication skills as diagnostic indicators for ASD at 12 months, and investigate whether it is possible to distinguish between ASD and other high-risk groups (e.g. developmental delay) at this age.

Assessing early communication behaviours: structure and validity of the Communication and Symbolic Behaviour Scales-Developmental Profile (CSBS-DP) in 12-month-old infants.

BACKGROUND: Parent report instruments are frequently used for the identification of both 'at-risk' children and to support the diagnosis of communication delay. Whilst the evidence is strong for the accuracy of parent report of vocabulary between 2 and 3 years, there are fewer studies that have considered the ability of parents to report on early communication behaviours in 12-month-old infants. AIMS: To investigate the validity of the underlying structure of the Communication and Symbolic Behaviour Scales-Developmental Profile (CSBS-DP) for each of the direct observation and parent reports of communication behaviour in infants at 12 months of age. METHODS & PROCEDURES: Participants were 1725 infants, already participating in a longitudinal study of language development, whose parents completed the Infant-Toddler Checklist from the CSBS-DP. Seven hundred and twenty-eight (728) of these infants also completed the Behaviour Sample from the CSBS-DP. The structure of the CSBS-DP was examined using confirmatory factor analyses (CFA) of the Behaviour Sample and the Infant-Toddler Checklist. Correlations between the Infant-Toddler Checklist and the Behaviour Sample on the total, composite, and subscale scores were also calculated. OUTCOMES & RESULTS: Confirmatory factor analysis of the CSBS-DP Behaviour Sample replicated previous work conducted during the development of the instrument, but on a larger and younger cohort of Australian infants. The data provided support for at least three factors, broadly representing Social, Speech, and Symbolic communication skills, with some evidence that the speech factor could be further split into sub-factors representing Sounds and Words. There was support for a three-factor structure for the Infant-Toddler Checklist. Moderate correlations were found between results from the Behaviour Sample and the Infant-Toddler Checklist. CONCLUSIONS & IMPLICATIONS: As measures of early communication skill for young infants, the CSBS-DP Behaviour Sample and the Infant-Toddler Checklist are valid clinical tools for measuring constructs broadly representing Social, Speech, and Symbolic communication skills. The Speech composite in particular emerged as a strong factor under the Behaviour Sample.