Digital archive of theses discussed at the University of Pisa


Thesis etd-05192015-145738

Thesis type
Tesi di specializzazione (5 anni)
Thesis title
Application of a broadband behavior rating scale (ITSEA)in under-threes with Autism Spectrum Disorder
Course of study
relatore Prof. Muratori, Filippo
  • Autism Spectrum Disorder; Toddlers; ITSEA; Early d
Graduation session start date
Research studies focused on early signs of Autism Spectrum Disorder (ASD) have seen an incredibly growth in the last decades. The findings have demonstrated the great heterogeneity of expression of core and co-occurring symptoms, of their onset, course and severity and the involvement of skills across multiple developmental domains. Early detection is of utmost importance to increase our knowledge of the neurobiological underpinnings of ASD as well as to allow early intervention with the purpose of preventing the full phenotypic expression of the disorder.
Studies suggest that an Autism Spectrum Disorder diagnosis can be reliably made in the second year of life and these early diagnoses appear to be relatively stable over time. However early detection and diagnosis still remain a big challenge in reason of the clinical heterogeneity and due to the overlap of symptoms such as temperament difficulties, emotional dysregulation, regulatory and attentional problems, cognitive and language delay. As a consequence, tools able to characterize and identify young children (infants and toddlers) with or suspected of ASD are widely needed.

The Infant-Toddler Social and Emotional Assessment (ITSEA, Carter & Briggs-Gowan, 2006) is a broadband parent-report rating scale developed specifically to identify social-emotional problems and competencies in children between 12 and 35 months of age; it includes three domains of Problems (Externalizing, Internalizing and Regulatory processes), one domain of Competencies and three indices (Atypical, Maladaptive behaviors, Social relatedness).

The main aim of this study is to define the profile of the Italian translation of the ITSEA in children under the age of three with ASD and to compare it with aged matched children with either typical development or non-asd neuro-psychiatric disorders (developmental delay or other psychiatric disorders).

The analysis and the characterization of the ITSEA profile in a group of 88 children (mean age 28.1, SD 5.9 months) with a diagnosis of ASD according to DSM-IV/DSM-5 criteria, were performed, with a qualitative comparison with the profile of an Autistic Disorder group (n=33, PDD-NOS excluded) provided in the ITSEA Manual and comparisons within ASD subgroups defined by age, gender and developmental level. Statistical comparisons (T-test for independent samples, ANOVA and Bonferroni post-hoc) with a Typical Development group (TD) of 60 children (mean age 26.8, SD 6.3 months) and two clinical groups (Developmental Delay (DD) group, n= 24, mean age 27.8, SD 6.2 months; Other Psychiatric Disorders (OPD) group, n=27, mean age 25.0, SD 7.0 months) were carried out, reporting preliminary data on accuracy (ROC analysis) of the ITSEA both as a screening tool and in the clinical use.
The application of an Italian translation of the brief version of the ITSEA (BITSEA, Briggs-Gowan & Carter, 2006) and its accuracy in discriminating ASD toddlers and TD toddlers have been also analyzed(T-test for independent samples, ROC analysis).

The ITSEA profile of the ASD group resulted similar to the one of the ITSEA Manual’s AD group and characterized by a global impairment of the Competence domain and clinical score in the Depression/Withdrawal scale and in the Social Relatedness and Atypical Item cluster. In our sample we found lower “of concern” percentages (scores in the clinical range) in comparison with the ITSEA Manual’s AD group. Different inclusion criteria (AD versus ASD) must be taken into account. The analysis within the subgroups defined by age have demonstrated an higher sensitivity of ITSEA in the younger group. Our results suggest a good capacity of the questionnaire in detecting Toddlers with ASD, with the Competence Domain as the most accurate index to distinguish the ASD toddlers from the TD toddlers (sensitivity of 72.0 % and specificity of 99.7 % considering the cut off at the 10th percentile, sensitivity of 80.5 % and specificity of 85 % considering the cut off at the 25th percentile). As expected, the Depression/Withdrawal subscale and the Atypical Item Cluster resulted specific for ASD, even if not as sensitive as the Competence domain. The results of the application of the BITSEA are consistent with the ITSEA findings: the Competence scale showed a good sensitivity (.88) and a fair specificity (.77); instead the BITSEA Problem scale showed an excellent specificity (.97), but a low sensitivity. In the comparison with the non-ASD group (union of DD and OPD groups) the Depression/Withdrawal subscale and the Atypical Item Cluster confirmed their specificity (94.1 % and 90.2 % , respectively) and a lower sensitivity (42% for both). The ITSEA profile can provide information about the core Autism symptoms (Atypical Behaviors, Withdrawal, Social Relatedness) as well as about a global impairment of competencies; it can also identify non-core autism symptoms as the temperamental, regulatory and externalizing difficulties.
Further studies with larger sample sizes are required to confirm these results and to suggest the validation of an Italian version of ITSEA/BITSEA as a supporting tool for early detection and assessment of ASD in toddlers.