Development of a language screening instrument for Swedish 4-year-olds

The Swedish Program for health surveillance of preschool children includes screening of language and communication abilities. One important language screening is carried out at age 4 years as part of a general screening conducted by health nurses at child health centres. The instruments presently in use for this screening mainly focus on expressive phonology. This may result in both over-referral of children with phonological difficulties and under-referral of children with language disorders (LDs), involving difficulties with vocabulary, grammar and/or language comprehension. Previous research has proposed non-word repetition as a clinical marker for LD. It has also been found that higher predictive power is achieved when non-word repetition is combined with the assessment of lexical/semantic skills. Taking these findings into account, the construction of a language screening instrument may yield more adequate referrals to speech-language therapists (SLTs).

To construct a new standardized language screening instrument for 4-year-olds and to test its properties.

An instrument was developed and revised after piloting. A population of 352 children was screened at the regular 4-year check-up by 11 health nurses. The final sample consisted of 328 children aged 46-53 months (23% multilingual). Children performing below a preliminary cut-off were referred to an SLT (n = 52). Five SLTs carried out an assessment on average within 5 weeks using a gold standard language test battery. Children who screened negatively were followed up with a parent questionnaire at age 5;6.

Thirty-one true-positives and 11 false-positives were identified after SLT assessment. A further six children were identified as false-negatives (two through referral to an SLT and four through parent questionnaire at age 5;6). A receiver-operating characteristics curve with a C statistic of .94 was calculated. Based on optimal cut-off, the sensitivity of the screening instrument was found to be .84, and specificity was .96. Multilingual children performed similar to monolingual children; boys performed significantly lower than girls; and children with a family history of language-related problems performed lower than those without. Interrater reliability was high, as was Cronbach's alpha.

The screening instrument seems sufficiently valid for its purpose to identify children who need further assessment by an SLT. A follow-up study including SLT assessment for all children to check for false-negatives would be interesting in future, as would studies comparing results from the 4-year screening with those from earlier screens.