Optimal intervention intensity.

Empirical evidence exists for many of the different interventions in speech-language pathology. However, relatively little is known about the optimal intensity of those interventions. In order for speech-language pathology services to be both effective and efficient speech-language pathologists need to know how to faithfully administer ideal doses of the active ingredients of interventions, in what forms, how often and for how long. This is the lead paper to a scientific forum on this fundamental yet under-studied issue of clinical practice. Borrowing from the work of Warren, Fey, and Yoder, the concept of intervention intensity is described. Issues involved in establishing the optimal intensity of interventions are identified, including what and how intervention goals are targeted. Given that speech-language pathology interventions can involve the delivery of therapeutic inputs (e.g., conversational recasts, questions) and/or clients carrying out an act (e.g., speech production, voice production, comprehending, naming, swallowing), a framework is proposed for measuring all potential inputs and acts that might contribute to the calculation of an intervention intensity. Client-, clinician-, condition-, and service-related variables that could influence the investigation and practical application of an optimal intervention intensity are also discussed.