“Captain Grey and the Greedy Aliens”: Obtaining normative data on a new test for the production of verbs at sentence level in children

Background: Children with specific language impairment (CwSLI) exhibit significant difficulties in language ability affecting areas such verb knowledge and verb production, producing fewer verbs and verb argument structures than typically developing (TD) children. As verbs are critical to sentence production it is also not surprising that they also produce fewer complex sentences. Although these areas of impairment are widely acknowledged there is a dearth of clinically available instruments that comprehensively assess verbs production and complex sentences in this population. Aims: To gather normative data from typically developing children aged 4;06-12;00 on their sentence complexity and production of verbs and their related argument structures using the newly developed story retell tool ‘Captain Grey and the Greedy Aliens’; to investigate the sensitivity of the assessment across the age ranges; to investigate the inter-rater reliability and clinical utility of the assessment; and finally to investigate the relationship between verb knowledge and verb argument structure accuracy and sentence complexity. Method &Procedure: Normative data was gathered on 91 typically developing children aged 4;06-12;00 using the story retell assessment; Captain Grey and the Greedy Aliens. Participant’s verb knowledge was also assessed via the Test of Verb Knowledge to allow for investigation of the relationship between verb knowledge and verb argument structure accuracy and sentence complexity. Outcome & Results: The story retell assessment was sensitive to developmental progression across age groups for mean accuracy of verb argument structures production and mean sentence complexity and was found to be highly reliable for inter-rater reliability. Positive relationships were found between verb knowledge and verb argument structure accuracy and sentence complexity. Conclusions & Implications: The story retell tool was shown to be effective in eliciting and analysing verb and verb argument structure production and sentence complexity. The data collected in this study can be used to provide normative data on this assessment however further sampling with larger sample sizes is warranted. Captain Grey and the Greedy Aliens may be a clinically useful tool.