A systematic review of treatment intensity in speech disorders

Purpose: Treatment intensity (sometimes referred to as "practice amount") has been well-investigated in learning non-speech tasks, but its role in treating speech disorders has not been largely analysed. This study reviewed the literature regarding treatment intensity in speech disorders.

Method: A systematic search was conducted in four databases using appropriate search terms. Seven articles from a total of 580 met the inclusion criteria. The speech disorders investigated included speech sound disorders, dysarthria, acquired apraxia of speech and childhood apraxia of speech. All seven studies were evaluated for their methodological quality, research phase and evidence level.

Result: Evidence level of reviewed studies ranged from moderate to strong. With regard to the research phase, only one study was considered to be phase III research, which corresponds to the controlled trial phase. The remaining studies were considered to be phase II research, which corresponds to the phase where magnitude of therapeutic effect is assessed. Results suggested that higher treatment intensity was favourable over lower treatment intensity of specific treatment technique(s) for treating childhood apraxia of speech and speech sound (phonological) disorders.

Conclusion: Future research should incorporate randomised-controlled designs to establish optimal treatment intensity that is specific to each of the speech disorders.