Complexity in measuring outcomes after communication partner training: Alignment between goals of intervention and methods of evaluation

Background: Researchers are currently discussing the need for consensus on a core set of outcome measures to assess interventions in aphasia. For indirect, environmental approaches to aphasia intervention, such as communication partner training (CPT), the roadmap to obtaining consensus on core outcome measures seems especially complex. While the purpose of CPT is to improve communication for people with communication disorders, the intervention is aimed at the communication partner. There is also a variety of goals, activities, and possible settings for CPT. This complexity increases the risk of a mismatch between the goals and content of the intervention and measures used to evaluate the outcome. Aims: The purpose of this paper is to describe the complexity of measuring outcomes from CPT. The aim is to enable clinicians and researchers to reflect on the outcomes to be measured and also on how different types of measures may or may not be aligned with the goals and content of a specific CPT intervention. Main contribution: The current proliferation of outcome measures used in CPT is considered in the light of a survey of general factors to be considered in evaluating intervention outcomes. The complexity of measuring outcomes in CPT is illustrated and the importance of alignment of main objectives, intervention tasks, and projected outcomes is exemplified by referencing two common types of CPT approaches. Objectives relating to knowledge of aphasia, interactional behaviour, and feelings and attitudes are considered in relation to specific outcome measurements. It is suggested that both study-specific and more general measures are needed for capturing and comparing outcomes. The measurement of relevant outcome in CPT is discussed along with implications for future research and clinical practice. Conclusions: Different CPT approaches share the same purpose of facilitating communication in aphasia, but their application in research studies or in the clinic, is specific to the particular context. Special care must thus be taken in both clinical practice and research to safeguard the alignment between objectives, tasks, and projected intervention outcomes and the actual measures used. Further, it is concluded that there is a need for the development of new measures based on a consensus on key outcomes to be measured in CPT