Assessment Fidelity in Aphasia Research.

Purpose: In aphasia treatment literature, scarce attention is paid to factors that may reduce a study's validity, including adherence to assessment and treatment procedures (i.e., fidelity). Although guidelines have been established for evaluating and reporting treatment fidelity, none exist for assessment fidelity.

Method: We reviewed treatment fidelity guidelines and related literature to identify assessment fidelity components. We then examined 88 aphasia treatment studies published between 2010 and 2015 and report the frequency with which researchers provide information regarding the following assessment fidelity components: assessment instruments, assessor qualifications, assessor or rater training, assessment delivery, assessor or rater reliability, and assessor blinding.

Results: We found that 4.5% of studies reported information regarding assessment instruments, 35.2% reported information regarding assessor qualifications, 6.85% reported information regarding assessor or rater training, 37.5% reported information regarding assessor or rater reliability, 27.3% reported on assessor blinding, and no studies reported information regarding assessment delivery.

Conclusions: There is a paucity of assessment fidelity information reported in aphasia treatment research. The authors propose a set of guidelines to ensure readers will be able to evaluate assessment fidelity, and thus study validity.