What works: evidence-based intervention for children with speech sound disorders.

To provide alternatives to the widespread use of nonspeech oral motor exercises for childhood speech sound disorders, speech intervention approaches that have received the highest level of experimental scrutiny are reviewed. Efficacy research over the past decade is critically evaluated according to hierarchical systems for quality and credibility. High standards for adherence to experimental methods are applied and reveal strong evidence for a variety of interventions that are effective. These approaches are organized according to whether their focus is directly on speech or indirectly on speech through language. Answers to the question, "What works?" with respect to features such as target selection strategies and teaching procedures are provided. Recommendations for selecting an evidence-based intervention are developed with consideration of developmental level and differential diagnostic evidence of speech sound disorder subtypes.