Did you know that the research design for the DSM-5 field trials is seriously flawed? The DSM-5 field trials are currently underway to evaluate the proposed revisions. In these trials, the DSM-5 work groups are evaluating test-retest and interrater reliability of the disorders.
They are not evaluating "diagnostic concordance." This means that the DSM-5 proposals are not being compared to disorders in the DSM-IV, DSM-III-R, DSM-III, and ICD-10 (which has been done in previous DSM revisions). Diagnostic concordance is like "convergent validity" – for example, the Beck Depression Inventory-II (BDI-II) has strong convergent validity with BDI (first edition). This supports overall construct validity in that both instruments are measuring the same construct.
For the DSM, diagnostic concordance can also predict prevalence rate changes for the proposed revisions. For example, a study by Mewton et al. (2011) compared the DSM-5's new "substance use disorder" with the DSM-IV's disorder and found a 60% increase in prevalence rate in those who can be diagnosed with the new DSM-5 disorder. This is a huge difference and should have implications as to the disorder's inclusion in DSM-5.
Many of the DSM-5 proposed revisions have lowered the number of symptoms and/or symptom duration needed for a diagnosis. This includes major depression, generalized anxiety disorder, substance use disorder, ADHD, pathological gambling, and more. Reducing the number of symptoms and symptom duration makes it easier to diagnose someone with a mental disorder – so it would seem that the prevalence of these disorders would increase, right?
So why did the DSM-5 Task Force purposely choose not to evaluate diagnostic concordance? Why did they choose to not evaluate changes in prevalence rates for the proposed revisions?
I’m interested in hearing your thoughts.
K. Dayle Jones is a counselor and associate professor at the University of Central Florida. She is acting chair of the American Counseling Association’s DSM Task Force, which was formed to provide feedback to the American Psychiatric Association on proposed revisions to the DSM-5. Contact her at firstname.lastname@example.org.