On Diagnostic Accuracy in Audiology: Central Site of Lesion and Central Auditory Processing Disorder Studies

Background: In the field of audiology a test protocol (index test) is used to determine the presence or absence of a target condition. The value of an index test rests in its diagnostic accuracy. Results from an index test must be verified through the use of a reference standard. The clinician and researcher should determine the quality and applicability of diagnostic accuracy studies. The Standards for Reporting of Diagnostic Accuracy (STARD) statement was published in response to the low quality of research conducted across many fields of study. It provides guidelines for the development and interpretation of diagnostic accuracy studies. Purpose: The primary purpose of this article is to assess the degree to which the main principles of diagnostic accuracy studies are used for the detection of central auditory nervous system lesions and a central auditory processing disorder (CAPD). The secondary purpose is to compare the design of these studies to select key guidelines from the STARD statement. The third purpose of this article is to present an argument against the reassignment of diagnostic accuracy values of a particular index test for one target condition (e.g., a central site of lesion) to a different target condition (e.g., a CAPD). Results: A review of diagnostic accuracy literature on the detection of a central site of lesion reveals the use of a reference standard for the independent verification of the index test results. However, diagnostic accuracy studies involving index tests for the detection of a CAPD show that independent verification of index test results is nonexistent or at best questionable. Conclusion: For a particular index test, while the diagnostic accuracy for detection of a central site of lesion may have been determined appropriately, it is inappropriate to reassign these diagnostic accuracy values to a different diagnostic target such as a CAPD.