Clinical Trials, Ototoxicity Grading Scales and the Audiologist's Role in Therapeutic Decision Making

Objectives: Define clinical trials and adverse event (AE) monitoring from the perspective of the audiologist. Rationalise the importance of audiology's involvement before, during and after monitoring. Identify strengths and weaknesses in toxicity grading scales, and discuss factors that may influence these.

Design: Literature involving commonly cited grading scales used to capture ototoxicity is reviewed. Current regulations and language associated with clinical trial implementation and AE monitoring are described. Personal observations based on a variety of clinical populations are drawn from years of experience developing and employing ototoxicity monitoring protocols in a complex medical setting.

Results: Six commonly used grading scales for ototoxicity are systematically reviewed for strengths and weaknesses. Necessary considerations that inform selection of grading scales are presented. A review of and historical context for clinical trial development and AE monitoring is provided.

Conclusions: The audiologist's role in therapeutic decision making goes beyond collection of the audiogram. Clear communication to stakeholders in ototoxicity monitoring is paramount, and toxicity grading scales are one tool to facilitate this exchange. Various factors should be considered in advance of selecting the most appropriate scale to capture hearing loss, and no scale is without limitation.