The Hierarchical Taxonomy of Psychopathology (HiTOP): A dimensional alternative to traditional nosologies.

The Hierarchical Taxonomy of Psychopathology (HiTOP) is a scientific effort to address shortcomings of traditional mental disorder diagnoses, which suffer from arbitrary boundaries between psychopathology and normality, frequent disorder co-occurrence, heterogeneity within disorders, and diagnostic instability. This paper synthesizes evidence on the validity and utility of the thought disorder and detachment spectra of HiTOP. These spectra are composed of symptoms and maladaptive traits currently subsumed within schizophrenia, other psychotic disorders, and schizotypal, paranoid and schizoid personality disorders. Thought disorder ranges from normal reality testing, to maladaptive trait psychoticism, to hallucinations and delusions. Detachment ranges from introversion, to maladaptive detachment, to blunted affect and avolition. Extensive evidence supports the validity of thought disorder and detachment spectra, as each spectrum reflects common genetics, environmental risk factors, childhood antecedents, cognitive abnormalities, neural alterations, biomarkers, and treatment response. Some of these characteristics are specific to one spectrum and others are shared, suggesting the existence of an overarching psychosis superspectrum. Further research is needed to extend this model, such as clarifying whether mania and dissociation belong to thought disorder, and explicating processes that drive development of the spectra and their subdimensions. Compared to traditional diagnoses, the thought disorder and detachment spectra demonstrated substantially improved utility: greater reliability, larger explanatory and predictive power, and higher acceptability to clinicians. Validated measures are available to implement the system in practice. The more informative, reliable and valid characterization of psychosis-related psychopathology offered by HiTOP can make diagnosis more useful for research and clinical care.

Traditional diagnostic systems went beyond empirical evidence on the structure of mental health. Consequently, these diagnoses do not depict psychopathology accurately, and their validity in research and utility in clinicalpractice are therefore limited. The Hierarchical Taxonomy of Psychopathology (HiTOP) consortium proposed a model based on structural evidence. It addresses problems of diagnostic heterogeneity, comorbidity, and unreliability. We review the HiTOP model, supporting evidence, and conceptualization of psychopathology in this hierarchical dimensional framework. The system is not yet comprehensive, and we describe the processes for improving and expanding it. We summarize data on the ability of HiTOP to predict and explain etiology (genetic, environmental, and neurobiological), risk factors, outcomes, and treatment response. We describe progress in the development of HiTOP-based measures and in clinical implementation of the system. Finally, we review outstanding challenges and the research agenda. HiTOP is of practical utility already, and its ongoing development will produce a transformative map of psychopathology.

A useful taxonomy of psychopathology should not only describe variations in mental disorder, but also explain how they occur and point to therapeutic solutions. Contemporary diagnostic models based on a system of polythetic disorder categories do not validly capture the covariation of disorders and symptoms across people, introducing both disorder comorbidity and het­erogeneity. As a result, significant advances in explaining dis­crete categories of psychopathology or deriving disorder-specific therapeutic solutions have not been forthcoming. These failures have led to new approaches to psychiatric taxonomy, such as the Research Domain Criteria (RDoC)1 and the Hierarchical Taxonomy of Psychopathology (HiTOP)2. Both of these systems conceptualize symptoms and disorders as dimensions that can be arranged hierarchically, with narrow symptoms being related to one another because of their mutual associations with broader domains. By reconfiguring mental health variables, HiTOP and RDoC provide evidence-based models of how people differ from one another on average and enable more reliable predictions about what kinds of dysfunctions people are likely to experience. However, these models are missing two elements that are crit­ical for explaining mental health problems and generating treatments. First, whereas HiTOP and RDoC account for psychopathology solely in terms of elevated levels of certain signs and symptoms within the person, psychopathology manifests as a pattern of dynamic transactions between people and their environments3. Persons with psychotic symptoms misperceive information about the world around them; persons with anxious symptoms experience benign situations as threatening; persons with antisocial features experience dangerous situations as exciting, often increas­ing risks to self and others. Second, neither RDoC nor HiTOP conceptualize how people move dynamically through their lives. Mental health problems and associated dysfunction are generally not constant. They are more often evoked and manifest in certain situational contexts. The psychotic person misperceives certain kinds of things, the anxious person usually worries about certain kinds of problems, and the antisocial person seeks certain kinds of thrills. HiTOP and RDoC can make predictions about which people are more or less likely to experience mental health problems in the abstract, but not when, where, and how these problems will manifest in the situations people encounter in their lives. Contemporary integrative interpersonal theory (CIIT) is a mod­el of personality and psychopathology built on 70 years of evidence regarding how people differ from one another (what people are like) and how they function in environmental contexts (what people do)4. Like HiTOP and RDoC, it provides a taxonomic model and suite of well-validated tools for assessing individual differences in personality and psychopathology5. However, in contrast to HiTOP and RDoC, CIIT is fundamentally concerned with how people function in the context in which they live. The model has two key features that complement new approaches to diagnosis. First, CIIT is essentially relational. The transition from understanding individuals in a vacuum to understanding people in context has been a stepping stone across scholarly pursuits. Philosophy became intersubjective when the existentialists understood that Descartes had to be thinking about something. The periodic table was derived from the principle that electrons serve the function of connecting elements with one another. Nuclear power was enabled by Einstein's insight about the connection between energy and time. Major models of psychopathology still operate on the assumption that mental disorder can be understood as something that occurs in a vacuum. In contrast, the first assumption of CIIT is that fundamentally important functional expressions of personality and psychopathology occur in interpersonal situations6. In CIIT, the interpersonal situation – encompassing direct in-person interactions with objects in the environment, most centrally other people, as well as mental representations of interactions, both recollected and imagined – is considered the basic unit of personality and psychopathology5. In the interpersonal situation, self and other interact through four interpenetrating systems that account for the important features of socio-affective function and dysfunction. Each system is represented by two-dimensional circular (circumplex) planes reflecting the major empirically supported dimensions of interpersonal functioning or emotion. The self system is structured by the individual's agentic and communal motives. The affect system is organized around the person's level of emotional arousal and valence. The behavior system includes each person's behavioral dominance and warmth. The perception system reflects each person's perceptions of agency and communion in themselves and the other. The interactions among these systems mark key components of dyadic processes that drive an interpersonal situation, as self and other dynamically cycle through continuous transaction. Second, CIIT is fundamentally dynamic. It is assumed that the satisfaction of motives for agency (power, status) and communion (connection, love) drive interpersonal behavior. This leads to specific, probabilistic predictions about how people will tend to transact with others via affective, behavioral and perceptual processes, and how that can go wrong. Adaptive functioning is not defined by dispositional levels per se: rather, it is defined by the ability to stably yet flexibly coordinate and satisfy self and others' motives within the contexts of developmental, socio-cultural and situational demands. Accordingly, dysfunction reflects sustained breakdown in any of the processes that support and maintain the flexible, stable and effective regulation of self, affect and/or interpersonal behavior. Circumplex measurement tools have been developed to capture variation in the self, affect and behavior system, and multi-perspective assessments can be used to capture variations in perception. Such tools include self- and informant-report questionnaires and rating scales, experience sampling via mobile devices, and computer-facilitated continuous observational assessment methods7. The dimensions of CIIT and its associated assessment methods can be used to distinguish people from one another, on average, as in HiTOP or RDoC, but they can also be used to describe how people vary from themselves across time and situations. These methods allow for empirical tests of hypotheses about dynamics in group-based research and in individual clinical cases. Parameters from validated dynamic interpersonal assessment measures have been empirically related to dysfunction8 and psychotherapeutic processes9. CIIT moves beyond models that describe how people differ from one another on average, and how those differences pose risk for symptoms, to also account for the context in which those symptoms manifest, and what kinds of environmental transactions can exacerbate or alleviate them. By marrying a structural model of individual differences with a functional model of person-environment transactions, CIIT supports a fuller understand­ing of personality, psychopathology and intervention, and pro­vid­es a relational and dynamic complement to individual-based models such as HiTOP and RDoC.

Diagnosis is a cornerstone of clinical practice for mental health care providers, yet traditional diagnostic systems have well-known shortcomings, including inadequate reliability, high comorbidity, and marked within-diagnosis heterogeneity. The Hierarchical Taxonomy of Psychopathology (HiTOP) is a data-driven, hierarchically based alternative to traditional classifications that conceptualizes psychopathology as a set of dimensions organized into increasingly broad, transdiagnostic spectra. Prior work has shown that using a dimensional approach improves reliability and validity, but translating a model like HiTOP into a workable system that is useful for health care providers remains a major challenge. The present work outlines the HiTOP model and describes the core principles to guide its integration into clinical practice. Potential advantages and limitations of the HiTOP model for clinical utility are reviewed, including with respect to case conceptualization and treatment planning. A HiTOP approach to practice is illustrated and contrasted with an approach based on traditional nosology. Common barriers to using HiTOP in real-world health care settings and solutions to these barriers are discussed. HiTOP represents a viable alternative to classifying mental illness that can be integrated into practice today, although research is needed to further establish its utility. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

The Hierarchical Taxonomy of Psychopathology (HiTOP) has emerged out of the quantitative approach to psychiatric nosology. This approach identifies psychopathology constructs based on patterns of co-variation among signs and symptoms. The initial HiTOP model, which was published in 2017, is based on a large literature that spans decades of research. HiTOP is a living model that undergoes revision as new data become available. Here we discuss advantages and practical considerations of using this system in psychiatric practice and research. We especially highlight limitations of HiTOP and ongoing efforts to address them. We describe differences and similarities between HiTOP and existing diagnostic systems. Next, we review the types of evidence that informed development of HiTOP, including populations in which it has been studied and data on its validity. The paper also describes how HiTOP can facilitate research on genetic and environmental causes of psychopathology as well as the search for neurobiologic mechanisms and novel treatments. Furthermore, we consider implications for public health programs and prevention of mental disorders. We also review data on clinical utility and illustrate clinical application of HiTOP. Importantly, the model is based on measures and practices that are already used widely in clinical settings. HiTOP offers a way to organize and formalize these techniques. This model already can contribute to progress in psychiatry and complement traditional nosologies. Moreover, HiTOP seeks to facilitate research on linkages between phenotypes and biological processes, which may enable construction of a system that encompasses both biomarkers and precise clinical description.

Quantitative, empirical approaches to establishing the structure of psychopathology hold promise to improve on traditional psychiatric classification systems. The Hierarchical Taxonomy of Psychopathology (HiTOP) is a framework that summarizes the substantial and growing body of quantitative evidence on the structure of psychopathology. To achieve its aims, HiTOP must incorporate emerging research in a systematic, ongoing fashion. In this article, we describe the historical context and grounding of the principles and procedures for revising the HiTOP framework. Informed by strengths and shortcomings of previous classification systems, the proposed revisions protocol is a formalized system focused around three pillars: (a) prioritizing systematic evaluation of quantitative evidence by a set of transparent criteria and processes, (b) balancing stability with flexibility, and (c) promoting inclusion over gatekeeping in all aspects of the process. We detail how the revisions protocol will be applied in practice, including the scientific and administrative aspects of the process. Additionally, we describe areas of the HiTOP structure that will be a focus of early revisions and outline challenges for the revisions protocol moving forward. The proposed revisions protocol is designed to ensure that the HiTOP framework reflects the current state of scientific knowledge on the structure of psychopathology and fulfils its potential to advance clinical research and practice. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

The utility of hierarchical models of psychopathology in genetics and biomarker research.

The Hierarchical Taxonomy of Psychopathology (HiTOP) represents a crucial step forward in the empirical refinement of psychiatric nosology. Although grounded in factor analyses of clinical symptoms and affiliated traits, HiTOP encourages research using measures of other types, including neural-system variables, to clarify coherent processes contributing to the hierarchical structure of psychopathology. However, systematic strategies for interfacing HiTOP dimensions with neural-system variables have not been put forth. We discuss reasons for considering neurobiological systems in relation to HiTOP (i.e. 'why') and propose alternative strategies that might be used to develop an interface between HiTOP and neurobiology (i.e. 'how'). In particular, we highlight potential advantages and limitations of establishing this interface through reference to (i) HiTOP dimensions themselves, or conventional personality trait models linked to HiTOP; (ii) alternative trait constructs designed to link conventional personality models and neurobiological measures; and (iii) mechanistic models of neurobiological processes relevant to HiTOP constructs, derived from computational modelling. We discuss the importance of establishing an interface between HiTOP and neurobiology to develop a more comprehensive, mechanistic understanding of psychopathology and to guide the refinement of the HiTOP model. Such efforts have the potential to guide the development and provision of effective, individualized psychological treatment.

The Hierarchical Taxonomy of Psychopathology (HiTOP) organizes phenotypes of mental disorder based on empirical covariation, offering a comprehensive organizational framework from narrow symptoms to broader patterns of psychopathology. We argue that established self-report measures of psychopathology from the pre-HiTOP era should be systematically integrated into HiTOP to foster cumulative research and further the understanding of psychopathology structure. Hence, in this study, we mapped 92 established psychopathology (sub)scales onto the current HiTOP working model using data from an extensive battery of self-report assessments that was completed by community participants and outpatients (N = 909). Content validity ratings of the item pool were used to select indicators for a bifactor-(S-1) model of the p factor and five HiTOP spectra (i.e., internalizing, thought disorder, detachment, disinhibited externalizing, and antagonistic externalizing). The content-based HiTOP scales were validated against personality disorder diagnoses as assessed by standardized interviews. We then located established scales within the taxonomy by estimating the extent to which scales reflected higher-level HiTOP dimensions. The analyses shed light on the location of established psychopathology scales in HiTOP, identifying pure markers and blends of HiTOP spectra, as well as pure markers of the p factor (i.e., scales assessing mentalizing impairment and suspiciousness/epistemic mistrust).

Research on trauma exposure and its consequences has made tremendous progress in elucidating the role of traumatic life events in the development and maintenance of psychopathology as well as in evaluating interventions aimed at addressing the personal and public burden of trauma-related psychopathology. However, there is growing concern that problems with predominant definitions of posttraumatic syndrome (e.g., content coverage and scope, within-category heterogeneity, excessive diagnostic comorbidity) limit further efforts to fully conceptualize trauma-related psychopathology and deliver appropriate, personalized interventions. As demonstrated by an impressive body of research over the past several years, the Hierarchical Taxonomy of Psychopathology (HiTOP) presents a compelling alternative to traditional nosologies in terms of empirically based characterizations of psychopathology phenotypes, with evidence of strong utility for research and clinical applications. However, HiTOP's primary focus on descriptive psychopathology has resulted in an unacceptable gap regarding the conceptualization of trauma-related psychopathology from a dimensional, transdiagnostic perspective. We see an important opportunity to clarify what HiTOP can offer the field of traumatic stress research and articulate a future for trauma-related psychopathology within HiTOP. We argue for disaggregating psychopathology symptoms from their purported causes and, instead, developing a detailed taxonomy of traumatic events alongside an ever-evolving HiTOP model. Doing so will help identify empirically based phenotypes of trauma-related psychopathology that (a) go beyond the traditional PTSD criterion sets and (b) allow for the possibility that different features of traumatic experiences (e.g., type, duration, subjective meaning) may be associated with different symptom sequelae across different psychopathology spectra.

Previous research has linked biased and inflexible interpretations of ambiguous information to various forms of psychopathology. However, existing studies typically investigate these interpretation processes within individual diagnostic categories, overlooking the significant symptom overlap and comorbidity among mental health conditions. Consequently, the extent to which biased and inflexible interpretations represent broad transdiagnostic or more narrowly specific risk factors remains unclear. To address this gap, this study investigated transdiagnostic associations between biased and inflexible interpretation processes and dimensions of psychopathology using the Hierarchical Taxonomy of Psychopathology (HiTOP). HiTOP is a data-driven framework designed to integrate psychopathology symptoms across traditional diagnostic boundaries. A crowdsourced community sample of adults (N=383) completed a HiTOP self-report battery and the emotional Bias Against Disconfirmatory Evidence task. This task measures negative and positive interpretation biases, as well as inflexible negative interpretations in social contexts. Bi-factor latent regression modeling was employed to examine associations between interpretation processes and both the general p-factor of psychopathology (an overarching dimension representing shared variance across disorders) and five HiTOP spectra (internalizing, thought disorder, disinhibited externalizing, antagonistic externalizing, detachment). The p-factor showed significant associations with negative interpretation bias and negative interpretation inflexibility. Reduced positive interpretation bias was uniquely associated with the detachment spectrum, which is characterized by emotional detachment, social disinterest, and avoidance of social relationships. These findings suggest that negatively biased and inflexible interpretations may represent general transdiagnostic risk markers for psychopathology, while reduced positive interpretation bias could be a more specific risk factor for detachment-related conditions. Future research should explore the mechanisms through which inflexible interpretation processes contribute to generalized and spectrum-specific psychopathological risk.

The Hierarchical Taxonomy of Psychopathology (HiTOP) is an empirically based, hierarchical model of the structure of psychopathology that was created in response to the limitations of traditional, categorical psychiatric classification frameworks. The HiTOP model has become increasingly popular in clinical psychology and psychiatry since its publication in 2017. In this Review, we consider the applicability of the HiTOP model to diverse, underrepresented and epistemically excluded populations. We first review the philosophy underlying psychopathology research in general to understand the impact of scientific norms on the inclusion of diverse populations within the research canon. We then review the HiTOP approach to modelling psychopathology, and how diverse populations have been included within HiTOP-related research to date. We conclude by highlighting ways for future research to increase the applicability of the HiTOP framework to diverse populations. Seriously engaging with the HiTOP model’s suitability for diverse, underrepresented and epistemically excluded populations is imperative in order to achieve the HiTOP consortium’s goal of delineating a fully empirical classification of psychopathology, and to provide a model that can guide the field of psychopathology research and training to increase representation. The Hierarchical Taxonomy of Psychopathology (HiTOP) is an empirically based, hierarchical model of the structure of psychopathology. In this Review, Rodriguez-Seijas et al. consider the applicability of the HiTOP model to diverse, underrepresented and epistemically excluded populations.

In their response to our article (both in this issue), DeYoung and colleagues did not sufficiently address three fundamental flaws with the Hierarchical Taxonomy of Psychopathology (HiTOP). First, HiTOP was created using a simple-structure factor-analytic approach, which does not adequately represent the dimensional space of the symptoms of psychopathology. Consequently, HiTOP is not the empirical structure of psychopathology. Second, factor analysis and dimensional ratings do not fix the problems inherent to descriptive (folk) classification; self-reported symptoms are still the basis on which clinical judgments about people are made. Finally, HiTOP is not ready to use in real-world clinical settings. There is currently no empirical evidence demonstrating that clinicians who use HiTOP have better clinical outcomes than those who use the Diagnostic and Statistical Manual of Mental Disorders (DSM). In sum, HiTOP is a factor-analytic variation of the DSM that does not get the field closer to a more valid and useful taxonomy.

The Hierarchical Taxonomy of Psychopathology (HiTOP) is a dimensional nosological system that addresses key limitations with categorical frameworks, including heterogeneity, boundary, and comorbidity issues. The HiTOP consortium recently developed a new self-report instrument, the HiTOP-Self-Report Measure (HiTOP-SR), designed to operationalize the HiTOP model for use in research and clinical practice. In a set of preregistered analyses with a sample of clinical/community participants (75% female, 81% White), we explored the hierarchical structure of the HiTOP-SR scales using exploratory factor analysis (n = 637) and examined their associations with behaviors and experiences assessed in daily life (n = 531), such as affect, stress, impulsivity, energy, sleep quality, and social interactions. Findings indicate a nine-factor model, closely aligned with the HiTOP's current structure, best represented the measure. The hierarchical structure of the HiTOP-SR generally converges with the HiTOP model, with several key departures, particularly for historically understudied constructs. Furthermore, the HiTOP-SR facet scales and domains associated with individual differences in daily behavior and experiences as anticipated, highlighting the construct validity and the potential clinical utility of this new measure. Our results have implications not only for the structure, validity, and clinical utility of the HiTOP-SR but also raise broader questions about the underlying nature of psychopathology as represented by the HiTOP. (PsycInfo Database Record (c) 2026 APA, all rights reserved).

The hierarchical taxonomy of psychopathology (HiTOP) is a novel classification system that adopts both a dimensional and hierarchical approach to psychopathology to address shortcomings. However, the HiTOP framework is descriptive in nature and requires additional research to consider potential mechanisms for the onset and maintenance of psychopathology, such as cognitive-behavioral emotion regulation strategies. To redress this gap, a sample of 341 adults who endorsed ongoing mental health concerns completed self-report measures of emotion regulation strategies and psychopathology. The data revealed a three-spectra HiTOP model consisting of internalizing, thought disorder, and antagonistic externalizing. Results found that psychopathology was most strongly associated with avoidance, catastrophizing, expressive suppression, and self-blame. In contrast, adaptive strategies were generally unrelated to the HiTOP spectra. This pattern was strongest for internalizing, distress, and detachment. Fewer, yet noteworthy unique relationships between the strategies and specific spectra/subfactors were also found. These findings suggest that psychopathology may be best conceptualized as an overutilization of maladaptive emotion regulation strategies. Furthermore, the results indicate there is added benefit to considering these strategies within a hierarchical approach to psychopathology. These associations alert clinicians to potential treatment targets and contribute to an ongoing literature that seeks to identify underlying mechanisms of the structure of psychopathology.