Diagnostic Reliability, Diagnostic Interviewing Procedures

Because of the preceding disadvantages, formal diagnostic interviewing procedures are rarely used in actual clinical practice . Given their time intensive requirements in combination with mental health provider needs for time ef?cient evaluation and treatment, it is not surprising that diagnostic interviewing procedures are underutilized and sometimes unutilized in clinical practice. In reality, researchers and academicians studying the prevalence, course, prognosis, and treatment of mental disorders use these procedures almost exclusively.

THE SCIENCE OF CLINICAL INTERVIEWING, PART II: DIAGNOSTIC RELIABILITY AND VALIDITY As suggested in Chapter 6, the clinical interview is the cornerstone of diagnostic assessment. To put it bluntly, no self respecting mental health professional would ever consider diagnosing a client without conducting a clinical interview. Nevertheless, the scienti?c question remains: Does a diagnostic interview provide reliable and valid diagnostic data and thereby conclusions? In terms of judging the psychometric qualities of a given procedure, reliability refers to replicability and stability. If a procedure, such as a diagnostic interview, is reliable, it consistently produces the same result; two interviewers, interviewing the same client, would come up with the same clinical data and therefore the same diagnosis. Statistically speaking, it is a commonly agreed on fact that an instrument or procedure must be reliable for it to have a chance at being valid . It is also possible for a diagnostic interview procedure to be highly reliable but invalid-as in the case where two or more interviewers consistently agree on diagnoses, but the diagnoses are incorrect.