Abstract
This thesis comprises three studies focusing on Swedish school-age children with Specific Language Impairment (SLI). Sixty-one participants with SLI aged 8-12 years were recruited from all existing school language units for children with severe SLI in Stockholm, Sweden. This thesis presents the first Swedish study of family history in SLI and the first empirical study of a clinical marker for Swedish SLI, and contributes to the sparse amount of research studies focusing on reading skills in Swedish children with SLI.
In Study I, the family history of a broad phenotype in SLI was investigated, based on telephone interviews with the parents of the participants with SLI and of 100 matched controls. Significantly higher prevalence rates of language, literacy and social communication problems were found in three generations of SLI relatives as compared to relatives of the controls. In Study II, based on assessments of the participants with SLI and 86 controls, and family history interviews; non-word repetition was reported as a clinical marker for Swedish SLI and was reported to be associated with a family history of language and/or literacy problems. In Study III, reading skills in the participants with SLI were investigated and found to be related to nonword repetition and to a family history of literacy problems in the parents.
The results, based on a large clinical sample with SLI, stress the importance of a family-focused approach to child language pathology. Knowledge about familial aggregation should be considered when making predictions about outcome, prevention and intervention.
