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The reliability and validity of traditional taxonomies are limited by arbitrary boundaries between psychopathology and normality, often unclear boundaries between disorders, frequent disorder co-occurrence, heterogeneity within disorders, and diagnostic instability. These taxonomies went beyond evidence available on the structure of psychopathology and were shaped by a variety of other considerations, which may explain the aforementioned shortcomings. The Hierarchical Taxonomy Of Psychopathology (HiTOP) model has emerged as a research effort to address these problems. It constructs psychopathological syndromes and their components/subtypes based on the observed covariation of symptoms, grouping related symptoms together and thus reducing heterogeneity. It also combines co-occurring syndromes into spectra, thereby mapping out comorbidity. Moreover, it characterizes these phenomena dimensionally, which addresses boundary problems and diagnostic instability. Here, we review the development of the HiTOP and the relevant evidence. The new classification already covers most forms of psychopathology. Dimensional measures have been developed to assess many of the identified components, syndromes, and spectra. Several domains of this model are ready for clinical and research applications. The HiTOP promises to improve research and clinical practice by addressing the aforementioned shortcomings of traditional nosologies. It also provides an effective way to summarize and convey information on risk factors, etiology, pathophysiology, phenomenology, illness course, and treatment response. This can greatly improve the utility of the diagnosis of mental disorders. The new classification remains a work in progress. However, it is developing rapidly and is poised to advance mental health research and care significantly as the relevant science matures.

Evidence suggests that the Hamilton depression scale is psychometrically and conceptually flawed. The breadth and severity of the problems militate against efforts to revise the current instrument. After more than 40 years, it is time to embrace a new gold standard for assessment of depression.

The expectation that Chinese people present distress somatically is a central prediction of cultural psychopathology and has been the subject of considerable theoretical speculation. At the same time, empirical studies have been infrequent and have yielded mixed results. The authors examined symptom presentation in Chinese (n=175) and Euro-Canadian (n=107) outpatients, using spontaneous problem report, structured clinical interview, and symptom questionnaire methods. All 3 methods yielded cross-culturally equivalent somatic and psychological symptom subscales. Chinese outpatients reported more somatic symptoms on spontaneous problem report and structured clinical interview compared with Euro-Canadians, who in turn reported more psychological symptoms on all 3 methods. The relation between culture and somatic symptom presentation was mediated by a tendency toward externally oriented thinking. Difficulties with identifying emotions or describing them to others did not differ significantly across cultures, supporting a nonpathological interpretation of observed differences. Psychological symptom effects were larger and more consistent than somatic symptom effects; because other studies have confirmed the ubiquity of somatic presentations worldwide, these results suggest that Western psychologization may be more culturally specific than is Chinese somatization.

Shortcomings of approaches to classifying psychopathology based on expert consensus have given rise to contemporary efforts to classify psychopathology quantitatively. In this paper, we review progress in achieving a quantitative and empirical classification of psychopathology. A substantial empirical literature indicates that psychopathology is generally more dimensional than categorical. When the discreteness versus continuity of psychopathology is treated as a research question, as opposed to being decided as a matter of tradition, the evidence clearly supports the hypothesis of continuity. In addition, a related body of literature shows how psychopathology dimensions can be arranged in a hierarchy, ranging from very broad "spectrum level" dimensions, to specific and narrow clusters of symptoms. In this way, a quantitative approach solves the "problem of comorbidity" by explicitly modeling patterns of co-occurrence among signs and symptoms within a detailed and variegated hierarchy of dimensional concepts with direct clinical utility. Indeed, extensive evidence pertaining to the dimensional and hierarchical structure of psychopathology has led to the formation of the Hierarchical Taxonomy of Psychopathology (HiTOP) Consortium. This is a group of 70 investigators working together to study empirical classification of psychopathology. In this paper, we describe the aims and current foci of the HiTOP Consortium. These aims pertain to continued research on the empirical organization of psychopathology; the connection between personality and psychopathology; the utility of empirically based psychopathology constructs in both research and the clinic; and the development of novel and comprehensive models and corresponding assessment instruments for psychopathology constructs derived from an empirical approach.

The paradigm of personality psychopathology is shifting from one that is purely categorical in nature to one grounded in dimensional individual differences. Section III (Emerging Measures and Models) of the Diagnostic and Statistical Manual of Mental Disorders (5th ed. [DSM-5]; American Psychiatric Association, 2013), for example, includes a hybrid categorical/dimensional model of personality disorder classification. To inform the hybrid model, the DSM-5 Personality and Personality Disorders Work Group developed a self-report instrument to assess pathological personality traits-the Personality Inventory for the DSM-5 (PID-5). Since its recent introduction, 30 papers (39 samples) have been published examining various aspects of its psychometric properties. In this article, we review the psychometric characteristics of the PID-5 using the Standards for Educational and Psychological Testing as our framework. The PID-5 demonstrates adequate psychometric properties, including a replicable factor structure, convergence with existing personality instruments, and expected associations with broadly conceptualized clinical constructs. More research is needed with specific consideration to clinical utility, additional forms of reliability and validity, relations with psychopathological personality traits using clinical samples, alternative methods of criterion validation, effective employment of cut scores, and the inclusion of validity scales to propel this movement forward.

Section 3 of the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) includes a hybrid model of personality pathology, in which dimensional personality traits are used to derive one of seven categorical personality disorder diagnoses. The Personality Inventory for DSM-5 (PID-5) was developed by the DSM-5 Personality and Personality Disorders workgroup and their consultants to produce a freely available instrument to assess the personality traits within this new system. To date, the psychometric properties of the PID-5 have been evaluated primarily in undergraduate student and community adult samples. In the current investigation, we extend this line of research to a psychiatric patient sample who participated in the APA DSM-5 Field Trial (Centre for Addiction and Mental Health site). A total of 201 psychiatric patients (102 men, 99 women) completed the PID-5 and the Revised NEO Personality Inventory (NEO PI-R). The internal consistencies of the PID-5 domain and facet trait scales were acceptable. Results supported the unidimensional structure of all trait scales but one, and the convergence between the PID-5 and analogous NEO PI-R scales. Evidence for discriminant validity was mixed. Overall, the current investigation provides support for the psychometric properties of this diagnostic instrument in psychiatric samples.

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