Expressive Language Sample Concordance With ADOS-2 Scores: Autism, Down Syndrome, Fragile X Syndrome

Area of Science:

• Developmental Psychology
• Linguistics
• Clinical Psychology

Background:

• The Expressive Language (EL) score was previously established using the Autism Diagnostic Observation Schedule, Second Edition (ADOS-2) Module administered and Item A1.
• Convergent validity of the EL score with other expressive language assessments for autism was demonstrated by Mazurek et al. (2019).

Purpose of the Study:

• To examine the relationships between the EL score and transcribed language samples in individuals aged 6 to 23 years.
• To assess the EL score's sensitivity to change over a 1-year period.
• To evaluate the EL score's validity across three diagnostic groups: autism, Down syndrome, and Fragile X syndrome.

Main Methods:

• The study analyzed transcribed language samples from individuals aged 6 to 23 years across three diagnostic groups.
• Expressive Language (EL) score relationships with language complexity, lexical diversity, talkativeness, and nonverbal participation were examined.
• Sensitivity to 1-year change was assessed by comparing EL scores over time.

Main Results:

• The EL score demonstrated convergent validity with measures of language complexity and lexical diversity.
• Variable patterns of divergence were observed between the EL score and measures of talkativeness and nonverbal participation.
• The EL score was not sensitive to 1-year changes, unlike the mean length of utterance in morphemes.

Conclusions:

• The EL score is useful for a rapid description of expressive language abilities.
• Caution is advised against using the EL score as a clinical outcome measure or a tool to track changes over time.
• Further research may explore the EL score's utility in specific clinical contexts and developmental stages.