The Spectrum Collaborative Project

The original project was based upon a 1995 Giovanni Cassano’s observation that there is a range of common clinical features that accompany each disorder classified in the Diagnostic and Statistical Manual of Mental Disorders (DSM), and that these features, even if not included in the diagnostic criteria might have clinical and research implications.

A major focus of the project was to develop and test instruments (structured interviews and self-report questionnaires) for the assessment of the spectrum of clinical features associated with the most relevant DSM mental disorders.

The proposed spectrum model highlighted since the beginning the significance of isolated, atypical symptoms and sub-threshold conditions that might be prodromals, precursors, sequelae, or might coexist with the core features of the disorder. Thus, such manifestations might have important implications for the course of illness, and for adherence and response to treatment.

What is the background and history of the spectrum model?

There has been great interest in the classification of mental disorders over the last 5 decades. Diagnostic criteria have been developed and described in the official international systems of classification, namely the Diagnostic and Statistical Manuals (DSM), and the Research Diagnostic Criteria (RDC). The adoption of a common language produced remarkable progresses in diagnostic reliability. However, these systems do not always succeed in capturing the complexity of clinical reality that emerges when comorbidity is considered or when symptoms are examined using a dimensional approach.

The option offered by the official categorical classifications does not entirely reflect the complexity of clinical reality. The diagnostic categories provide a useful but incomplete characterization of psychopathology. Impairment in work, family, and social functioning is often inadequately explained by symptoms of threshold-level disorders. Some subjects might experience substantial impairment even from isolated symptoms or sub-threshold manifestations surrounding the clinical core features of the disorders.

Moreover, the current system of categorization does not take into account the continuum between the criterion symptoms of a disorder and its prodromal, residual, atypical, or subclinical signs and features.

The original group of clinicians and researchers who started the ‘spectrum project’ proposed a new ‘spectrum model’ with the main aims to better characterize clinical reality, to improve clinical assessment and to help the clinicians in treatment choices, with a systematic assessment of subclinical and atypical features of diagnostic categories, the importance of which is often underestimated.

What is the relationship between spectrum and the current version of the DSM?

DSM-5 undoubtedly made an effort towards the integration between the ‘dimensional’ and the ‘categorical’ realms, enlarging the too strictly designed categories of the DSM-IV, adding a number of subcategories, and several ‘specifiers’ for each diagnosis. The implementation of DSM categories with the ‘other specified’ and ‘unspecified’ categories represents an attempt to give clinical significance to atypical and sub-threshold manifestations of mental disorders. The description of previously neglected features among the diagnostic criteria moves in the same direction. However, this effort towards a more refined description of dimensions enlarged the number of subcategories through a complex combination of coded courses and severity ‘specifiers’, only mimicking a dimensional rating.

The proposed spectrum model, with its interviews and questionnaires, explores the ‘core’ criterion diagnostic symptoms and their associated features, as well as the wide range of symptoms surrounding the typical features of mental disorders, in a unitary format. Findings suggest that the spectrum approach is able to offer clinicians a more clinically meaningful assessment of psychopathology than the established measures of mental disorders severity.

How is spectrum psychopathology assessed?

Spectrum assessment is based upon a concept that uses individual DSM criterion symptoms as a starting point, and extends the DSM description to encompass the halo of surrounding clinical phenomena. These include associated features described in the DSM as well as symptoms, maladaptive behavioral traits and temperamental features that do not appear in the DSM.
Spectrum assessment generates a dimensional profile as integrated to a categorical diagnosis, obviating the need for threshold-based definition.

Who was in the Original Conceptualization of the Spectrum Model?

The Spectrum Collaborative Project is born as an international project that involved clinicians and researchers from Italy and USA. The original participants in the project were Giovanni Battista Cassano, Liliana Dell’Osso, Mauro Mauri, Paola Rucci, Claudia Carmassi, Mario Miniati, Antonella Benvenuti, from the University of Pisa, Italy; David Kupfer, Ellen Frank, Mary K. Shear, Andrea Fagiolini, and Victoria J Grochocinskj, from the University of Pittsburgh, PA, U.S.A.; Jack D. Maser from the University of California, San Diego, CA, U.S.A.; and Jean Endicott from the Columbia University, NY, U.S.A.

The original line-up has changed.
Here the present of the spectrum project:

Principal Investigator

Liliana Dell’Osso, M.D.
Full Professor of Psychiatry, Director of Psychiatry, Department of Clinical and Experimental Medicine, University of Pisa, Italy. President of the National College of Professor of Psychiatry. She has been a principal invstigator of the Spectrum Collaborative Project since its inception and has substantially contributed to the development and validation of most of the Spectrum instruments.

Co-Investigators