Population-based screening of children for specific speech and language impairment in Germany: a systematic review.

OBJECTIVE The study was aimed at evaluating the effectiveness of a systematic population-based screening programme for specific language impairment (SLI) in preschool children in Germany. METHODS The study question was divided into a review of (1) evidence from studies evaluating screening programmes, (2) diagnostic instruments in the German language, and (3) studies evaluating speech and language interventions. A systematic database search was conducted between June and October 2007 and was updated in January and again in May 2008. Relevant studies were identified by 2 independent reviewers based on screened titles/abstracts and full texts. RESULTS 4,806 studies were screened. The only existing controlled screening study did not provide data for SLI. No diagnostic study met the inclusion criteria. Sixteen randomized intervention studies were included, 3 studies contributed to the appraisal of earlier against later initiation of treatment. Most studies were of limited quality. We found indications of short-term positive effects from language therapies in children with SLI. Long-term outcomes were not investigated. No evidence supporting the advantage of earlier treatment initiation was identified. CONCLUSIONS The benefit of population-based language screening of preschool children with SLI is not proven. Controlled screening studies are therefore necessary. For Germany, the accuracy of existing diagnostic instruments has not yet been sufficiently examined.