Comorbidity Among Mental Disorders: A New Approach

ECMental disorders have traditionally been viewed as distinct categorical entities, but about 50% of people who meet the criteria for one disorder also meet the criteria for a second disorder. The large number of people with comorbid disorders suggests there may be a simpler underlying structure to psychopathology than the one implied by the current classification system.

APS Fellow Avshalom Caspi (Duke University, Kings College London) and colleagues examined the structure of psychopathology using data from the Dunedin Multidisciplinary Health and Development Study — a prospective longitudinal study of health and behavior. Participants in the study were repeatedly assessed for mental health disorders between ages 18 and 38.

The authors tested several models using confirmatory factor analysis and found that a three-factor model comprised of an internalizing vulnerability to depression and anxiety, an externalizing vulnerability to antisocial and substance-use disorders, and a thought disorder vulnerability to symptoms of psychosis fit the data. The data was also well explained by a single general psychopathology dimension, which the researchers named the “p factor.”

According to the authors, a useful way to think about this general psychopathology factor is to relate it to the general factor of intelligence — the g factor. Under the umbrella of cognitive abilities are many dissociable and separate abilities such as verbal skills, working memory, and processing speed. Despite this, researchers find that the g factor accounts for the positive correlation between these separate abilities, explaining why people who do well on one measure of cognitive ability tend to do well on another.

The authors hypothesize that, similar to the g factor of cognitive ability, the p factor of psychopathology accounts for the presence or absence of psychiatric symptoms and summarizes people’s propensity to develop all types of psychopathology. In support of this proposal, the researchers found that the higher a person scores on the p factor, the worse they score on indicators of psychopathic severity, duration, comorbidity, and impairment.

A single-factor view of psychopathology may help explain why it has been so difficult to find causes, biomarkers, and treatments for individual mental disorders, and could help spur new research into the relationships between, and the structures of, common mental disorders.


Caspi, A., Houts, R. M., Belsky, D. W., Goldman-Mellor, S. J., Israel, S., Meier, M. H., … Moffitt, T. E. (2014).  Clinical Psychological Science, 2(2), 119–137. doi: 10.1177/2167702613497473


the name “p-factor” has been used before, also in reference to the g-factor. In this case the p referred to personality. See W.K.B. Hofstee’s 2001 chapter “Intelligence and personality: do they mix?”In J.M. Collis and S. Messick (eds.), Intelligence and personality: bridging the gap in theory and measurement, pp43-60. Mahwah, N.J., Erlbaum

Yet more fiction from the paranoid, analytical mind police of this world; people who would have diagnosed Jesus Christ a paranoid schizophrenic to say nothing of Mohammed and the Buddha. When is the World finally be ride of this arrogant, grandiose nonsense from this unholy band of intellectual narcissists who have perpetrated a worldwide genocide against original thinkers and people of integrity for decades, yet who have been proven to have contributed absolutely no net or authentic benefit to the condition of Mankind.

From neurosciences, we could explain this through the observation of the different areas of the human brain and all the connections among them. So, we could understand the enormous possibility of having some area not working well and the impact that this could be in other related areas.

Sorry for my English (not native speaker)

Greetings from México 🙂

In a research took place on 196 larynx cancer patients, it was found that the survival rate of patients at various stages of cancer differs counting on the presence or absence of comorbidity.

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