Controversies surrounding the diagnosis of schizophrenia and other psychoses.
ABSTRACT The diagnosis of schizophrenia and other psychotic disorders in current psychiatric classifications identifies individuals who are severely ill but who have few clinical characteristics in common. The usual picture of psychotic patients is a mixture of mood and psychotic symptoms. Fortunately, clinicians do not base their therapeutic strategies exclusively on diagnosis, but also on symptom predominance. Thus, clinicians' treatments have been dimensional in nature for years, although, until recently, their psychiatric classifications had been mainly categorical. The main principle in psychosis classification has been the Kraepelinian dichotomy, despite its lack of enduring empirical validation. Without doubt, current psychiatric classifications have made great strides in reliability and clinical utility, although these advantages have not been enough to compensate for their shortcomings concerning validity. It has recently been suggested that the Kraepelinian dichotomy may be hindering progress in neurobiological research within psychosis. Mounting evidence is now fuelling a paradigm shift in the ongoing process of review of psychiatric classifications toward the introduction of complementary dimensional indicators of psychiatric categorical diagnoses. This new approach will allow us to understand psychosis as prototypical extremes of a severity continuum. The gradients of this continuum may begin with subtle expressions in the general population, continue with milder forms in relatives of psychotic patients and subclinical cases and finally reach the prototypical forms of psychosis at the other extreme. Future complementary dimensional indicators will require sound instruments capable of reflecting a multidimensional assessment of psychopathological symptoms, polydiagnostic interviews and the assessment of a wide range of nonsymptomatic domains. These new methods of assessment merging created by the shift toward a dimensional paradigm will be applied in the forthcoming new diagnostic criteria and may allow for a phenome-wide scanning for psychosis.
[Show abstract] [Hide abstract]
ABSTRACT: Considering the widespread use of the Positive and Negative Syndrome Scale (PANSS) and its factors around the world in clinical trials, it is clearly necessary to perform a transcultural validation of the factor structure of the PANSS. The purpose of the present study was to examine the PANSS factor structure in a Korean sample of subjects with schizophrenia. A total of 150 outpatients were assessed using the PANSS and other clinical rating scales. Principal component analyses revealed five factors, i.e., negative, cognitive/disorganization, positive, excitement, and depression/anxiety dimensions, which accounted for 64.1% of the total variance. All five factors showed good internal consistency, suggesting that the reliability of the factors extracted was adequate. Significant correlations were found between the five components of the PANSS and the corresponding clinical rating scales. The results of the present study indicate that the five-factor model best fit the data from our patients and that it was validated transculturally. The factor structures should be further validated using various neurobiological methods to ultimately help in clarifying the heterogeneity and pathogenesis of symptomatology in schizophrenia.Psychiatry Research 02/2012; 197(3):285-9. DOI:10.1016/j.psychres.2011.10.006 · 2.68 Impact Factor
[Show abstract] [Hide abstract]
ABSTRACT: Although dementia praecox or schizophrenia has been considered a unique disease entity for more than a century, definitions and boundaries have changed and its precise cause and pathophysiology remain elusive. Despite uncertain validity, the construct of schizophrenia conveys useful clinical and etiopathophysiologic information. Revisions of the Diagnostic and Statistical Manual of Mental Disorders and the International Classification of Diseases seek to incorporate new information about schizophrenia and include elimination of subtypes, addition of psychopathological dimensions, elimination of special treatment of Schneiderian "first-rank" symptoms, better delineation of schizoaffective disorder, and addition of a new category of "attenuated psychosis syndrome".The Psychiatric clinics of North America 09/2012; 35(3):557-69. DOI:10.1016/j.psc.2012.06.001 · 1.87 Impact Factor
Epidemiology and Psychiatric Sciences 09/2013; 22(4):1-3. DOI:10.1017/S2045796013000498 · 3.36 Impact Factor