Study: Manual changes could result in false-negative diagnoses
Researchers at Rhode Island Hospital determined that recommended changes in the upcoming revision to the “Diagnostic and Statistical Manual, fifth edition” (DSM-5) could result in false-negative diagnoses.
In a paper published in the Journal of Clinical Psychiatry, the researchers examined the impact of deleting five personality disorders in the new DSM-5 – paranoid, schizoid, histrionic, narcissistic and dependent personality disorders. The deletions were among recommendations made by the DSM-5 Personality and Personality Disorders work group and were being looked at as a way to reduce the level of comorbidity among the disorders. (The work group has since decided to retain narcissistic personality disorder).
The study examined the impact the changes might have and indicated that while the new system would reduce the level of comorbidity, it would not eliminate it. Additionally, the changes could result in false-negatives.
The researchers evaluated 2,150 psychiatric outpatients, more than one-quarter of whom were diagnosed with one of the 10 DSM-IV personality disorders. They determined that if the five proposed disorders were removed, 59 patients who were diagnosed with a personality disorder according to the DSM-IV criteria would no longer be so diagnosed.
The researchers compared the level of psychosocial morbidity in patients with a retained or excluded personality disorder to each other and to patients without a personality disorder and there was little difference in psychosocial morbidity in the patients with the retained or excluded disorder – but in both of those groups it was greater than those without a personality disorder.
“Thereby implying that those individuals with an excluded disorder really should be considered to have a personality disorder,” says the study’s lead author, Mark Zimmerman, M.D., director of outpatient psychiatry at Rhode Island Hospital and associate professor at The Warren Alpert Medical School of Brown University. “And they really were indistinguishable from those individuals with the retained disorders. So it’s tough to put forward the empirical case that those disorders that were retained were more important than those that were excluded.”
One of the researchers, Kristy Dalrymple, Ph.D., says those patients meeting criteria for an excluded personality disorder diagnosis demonstrated greater severity and poorer functioning compared to patients with no personality disorder diagnosis, suggesting that important information with respect to clinical presentation and treatment prognosis may be lost if those patients were excluded from the personality disorder diagnosis.
“A lack of this information could affect aspects of treatment planning such as a psychiatrist determining whether a referral should be made for psychotherapy, a therapist determining whether a referral should be made for medication management or a therapist determining what types of psychotherapeutic approaches would best target an individual’s problems,” Dalrymple says. “Therefore, if someone experiences chronic problems related to one of these personality disorders slated for exclusion that underlie and perhaps exacerbate the acute problems related to an Axis I diagnosis, these problems may not be adequately identified and addressed.”
Zimmerman says he is concerned about changes being adopted in the manual without adequate evaluation. He says it has been suggested that no major damage will be done by eliminating these disorders because there aren’t that many treatment studies that have been designed to treat these personality disorders. “Just because there haven’t been specified treatment studies doesn’t mean that individuals don’t struggle with these traits and that clinicians aren’t addressing them in treatments,” he adds.