Specific Language Impairment and Early Second Language Acquisition: The Risk of Over- and Underdiagnosis

Abstract

Child and family risk factors of Specific Language Impairment (SLI), including delayed mastery of early language milestones and family history of language impairment, have been found to affect more SLI children than typically developing (TD) children. However, little to no research has examined whether prevalence differs between monolingual and early second language (eL2) learners. Furthermore, the degree of misdiagnosis in clinical settings is unknown as well as whether monolingual and eL2 children differ in the proportion of over- and underdiagnosis. The present study compared both language groups regarding the prevalence of risk factors and (mis)diagnosis as SLI. The sample included 92 monolingual (69 TD, 23 SLI) and 74 eL2 children (55 TD, 19 SLI), aged 5–8 years, and their parents. Prevalence of child/family risk factors was assessed via parental questionnaire; misdiagnosis was calculated by comparing children’s identification as (non)SLI via a standardized test with their clinical diagnosis. Except for dyslexia/dysgraphia, the rate of child and family risk factors was the same in both language groups, correctly identifying up to half of the SLI children. Correlation analyses between SLI-identification and clinical diagnosis indicated a moderate positive association. The rates of misdiagnosis in monolingual and eL2 children varied, with underdiagnosis being more frequent than overdiagnosis across groups. Moreover, the rate of overdiagnosis was marginally higher for eL2 children than for monolinguals. Summarizing, correct clinical diagnosis as SLI is difficult in both monolinguals and in eL2 learners; a correct diagnosis as unimpaired is especially challenging in eL2 children. Our results suggest that complementing standardized language assessments with parental information helps to reduce the rate of misdiagnosis in both types of learners.