Nav: Home

Research consortium develops evidence-based diagnostic model for mental illness

March 23, 2017

BUFFALO, N.Y. -- A consortium of psychologists and psychiatrists has developed a new, evidence-based alternative to the mental health field's long-established diagnostic tools for the classification, treatment, and research of mental disorders, according to a University at Buffalo psychologist who is one of the co-authors of a paper that explains the groundbreaking approach.

The Hierarchical Taxonomy of Psychopathology (HiTOP) addresses what the authors say are limitations to the reliability and validity of traditional models like the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), the American Psychiatric Association's (APA) authoritative handbook used by clinicians and researchers around the world to diagnose and treat mental disorders.

"HiTOP is the first attempt by any group of individuals to put forth a classification and diagnostic system that has the features we've described," says Leonard Simms, an associate professor in UB's Department of Psychology and one of the 40 researchers who worked with team leaders Roman Kotov of Stony Brook University, Robert Krueger of University of Minnesota, and David Watson of University of Notre Dame on the study that appears in the latest issue of the Journal of Abnormal Psychology.

, an expert in the description and classification of mental disorders, says the potentially paradigm-shifting model has the capacity to advance research efforts and improve clinical outcomes related to the causes and treatments of mental disorders.

HiTOP's guiding spirit is correcting the shortcomings of DSM-5 and other similar classification schemes, like the World Health Organization's International Classification of Diseases (ICD), by changing the way mental disorders are classified and diagnosed.

HiTOP uses a diagnostic approach that is dimensional and hierarchical. Traditional systems, like DSM-5, are categorical.

Categorical systems associate each disorder with a set of symptoms. Clinicians make a diagnosis of a disorder only when patients present an established minimum number of those symptoms. For instance, Major Depressive Disorder is associated with nine symptoms. At least five of those symptoms must be present for a patient to receive a diagnosis of Major Depressive Disorder.

"That's an arbitrary classification," says Simms. "Somebody with four symptoms of depression could be experiencing as much if not more impairment than someone who meets the five criteria. Yet five gets the diagnosis and four does not. You see this throughout DSM-5."

"I use a word like 'arbitrary' because in many cases the threshold in the diagnostic manual is usually half the number of symptoms. There is no evidence brought to bear on that threshold."

Forcing people into categories means losing critical information because of distinctions between symptoms and impairment. "That distinction creates a false negative," says Simms. "A patient can have one symptom of depression and still be impaired."

By eliminating arbitrary boundaries that separate either having a disorder or not having a disorder, researchers and clinicians can make more meaningful decisions.

Simms says statistical analysis shows that shades of gray, or dimensions, are more meaningful than categories. "There are a variety of statistical techniques that have been in use over the last 25 years that allow us to determine whether underlying symptoms are better described as a categorical or dimensional phenomenon, with the vast majority of that evidence favoring a dimensional approach to psychiatric classification," he says.

HiTOP's hierarchical component is based on analysis of symptom similarities. Any group of symptoms might be very close to others.

"There are various ways to talk about depression or anxiety," says Simms. "Statistics provide researchers with evidence-based ways of combining those symptoms or not. DSM-5 has more disorders than we need. It's not always clear how one disorder differs from another."

The core issue for the authors is that traditional systems have been shaped by considerations other than empirical evidence.

"A lot of this is inertia," says Simms. "We've had categories for mental disorders for decades, and that inertia has been an impediment to making changes in the way we think about the mental disorders."

It comes down to a system characterized by past practice.

"Imagine a physician saying, 'the research says we should do an MRI on your knee, but my training was in the 1970s, so we're going to take an X-ray and that's going to have to be good enough.' The same thing applies here. Many current clinicians are not being influenced by the evidence."

Simms says a system, like HiTOP, that's based on solid evidence is an advance all by itself.

"A diagnostic system that places people into these messy categories that aren't necessarily distinct from one another creates a lot of noise in the research world," he says. "We can make further advances in research into the causes and treatments of these disorders if we have an evidence-based system with known patterns of correlation among these symptoms.

"If we have a system that's cleaned up this way, not only would the research be stronger in terms of the causes and treatments of these disorders, but it presumably would lean toward better connections with different treatment modules that would be useful clinically."

The HiTOP classification system remains a work in progress, but several parts of the model are ready for clinical and research applications, according to Simms.

University at Buffalo

Related Mental Disorders Articles:

Are refugees at increased risk of developing mental disorders?
Whether the experience of being a refugee increases the probability of developing a mental disorder such as schizophrenia was the focus of this study, a systematic review and meta-analysis that combined the results of nine studies involving 540,000 refugees in Denmark, Sweden, Norway and Canada.
Rutgers collaborates with WHO to more accurately describe mental health disorders
A Rutgers University researcher collaborated with the World Health Organization on the first study to seek input from people with common mental health issues on how their disorders are described in diagnostic guidelines.
Articles focus on psoriasis, risk of mental health disorders
Two related articles and an editorial focus on the chronic inflammatory skin disorder psoriasis and the risk of mental health disorders.
Mental disorders more common in people who live alone
Living alone is positively associated with common mental disorders, regardless of age and sex, according to a study published May 1, 2019 in the open-access journal PLOS ONE by Louis Jacob from University of Versailles Saint-Quentin-en-Yvelines, France, and colleagues.
Mental health disorders rife in post-conflict areas
A new study has found that 58 percent of people displaced following the civil war in Sri Lanka have suffered mental health problems.
How common are mental health disorders after diagnosis of head and neck cancer?
Treatment for head and neck cancer (HNC) might cure the disease but it also can result in adverse effects such as disfigurement and speech difficulties, which can affect quality of life for patients.
Looking behind a rare brain disease for clues to treat more common mental disorders
Researchers have clarified, for the first time, the mechanism behind a very rare brain disorder called MICPCH (microcephaly, disproportionate pontine and cerebellar hypoplasia) syndrome in animal models.
How common are mental health disorders, treatment in children?
An estimated 7.7 million children in the United States (16.5 percent) have at least one mental health disorder and about half didn't receive treatment from a mental health professional.
Mental health disorders common following mild head injury
A new study reveals that approximately 1 in 5 individuals may experience mental health symptoms up to six months after mild traumatic brain injury (mTBI), suggesting the importance of follow-up care for these patients.
Researchers map out the relationship between mental disorders
Based on register data from 5.9 million people living in Denmark from 2000 to 2016, the study is the most detailed study of comorbidity ever conducted in the field of mental health.
More Mental Disorders News and Mental Disorders Current Events

Top Science Podcasts

We have hand picked the top science podcasts of 2019.
Now Playing: TED Radio Hour

In & Out Of Love
We think of love as a mysterious, unknowable force. Something that happens to us. But what if we could control it? This hour, TED speakers on whether we can decide to fall in — and out of — love. Guests include writer Mandy Len Catron, biological anthropologist Helen Fisher, musician Dessa, One Love CEO Katie Hood, and psychologist Guy Winch.
Now Playing: Science for the People

#542 Climate Doomsday
Have you heard? Climate change. We did it. And it's bad. It's going to be worse. We are already suffering the effects of it in many ways. How should we TALK about the dangers we are facing, though? Should we get people good and scared? Or give them hope? Or both? Host Bethany Brookshire talks with David Wallace-Wells and Sheril Kirschenbaum to find out. This episode is hosted by Bethany Brookshire, science writer from Science News. Related links: Why Climate Disasters Might Not Boost Public Engagement on Climate Change on The New York Times by Andrew Revkin The other kind...
Now Playing: Radiolab

An Announcement from Radiolab