Journal of Consulting and Clinical Psychology © 2019 American Psychological Association 2019, Vol. 87, No. 12, 1069–1084 ISSN: 0022-006X http://dx.doi.org/10.1037/ccp0000452 Integrating the Hierarchical Taxonomy of Psychopathology (HiTOP) Into Clinical Practice Camilo J. Ruggero Roman Kotov University of North Texas Stony Brook University Christopher J. Hopwood Michael First University of California, Davis Columbia University Lee Anna Clark Andrew E. Skodol University of Notre Dame University of Arizona Stephanie N. Mullins-Sweatt Christopher J. Patrick Oklahoma State University Florida State University Bo Bach David C. Cicero Slagelse Psychiatric Hospital, Slagelse, Denmark University of North Texas Anna Docherty Leonard J. Simms University of Utah University at Buffalo, The State University of New York R. Michael Bagby Robert F. Krueger University of Toronto University of Minnesota Jennifer L. Callahan Michael Chmielewski University of North Texas Southern Methodist University Christopher C. Conway Barbara De Clercq College of William and Mary Ghent University Allison Dornbach-Bender Nicholas R. Eaton University of North Texas Stony Brook University Miriam K. Forbes Kelsie T. Forbush Macquarie University University of Kansas John D. Haltigan Joshua D. Miller University of Toronto University of Georgia This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly. Leslie C. Morey Praveetha Patalay Texas A&M University University College London Camilo J. Ruggero, Department of Psychology, University of North Texas; of Notre Dame; Andrew E. Skodol, Department of Psychiatry, University of Roman Kotov, Department of Psychiatry, Stony Brook University; Christo- Arizona; Stephanie N. Mullins-Sweatt, Department of Psychology, Oklahoma pher J. Hopwood, Department of Psychology, University of California, Davis; State University; Christopher J. Patrick, Department of Psychology, Florida Michael First, Department of Psychiatry, New York State Psychiatric Institute, State University; Bo Bach, Psychiatric Research Unit, Slagelse Psychiatric Columbia University; Lee Anna Clark, Department of Psychology, University Hospital, Slagelse, Denmark; David C. Cicero, Department of Psychology, continued 1069 1070 RUGGERO ET AL. Darrel A. Regier Ulrich Reininghaus Uniformed Services University Maastricht University and King’s College London Alexander J. Shackman Monika A. Waszczuk University of Maryland Stony Brook University David Watson Aidan G. C. Wright University of Notre Dame University of Pittsburgh Johannes Zimmermann University of Kassel Objective: 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 psycho- pathology 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. Method: The present work outlines the HiTOP model and describes the core principles to guide its integration into clinical practice. Results: 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. Conclusions: 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. What is the public health significance of this article? Redefining a taxonomy of psychopathology according to data results in dimensions, not categories, that can be organized hierarchically—with at least six higher level spectra near the top of the model and more specific lower level components and traits at the bottom. This approach may improve case conceptualizations and align more closely with transdiagnostic treatments, while also specifying more narrow targets for intervention. A case illustration shows how the HiTOP model can be used in clinical practice today, although additional research is needed to fully assess the utility of this approach for providers and patients. Keywords: classification, diagnosis, nosology, psychopathology, treatment University of North Texas; Anna Docherty, Department of Psychiatry, Stress, Uniformed Services University; Ulrich Reininghaus, Department of University of Utah; Leonard J. Simms, Department of Psychology, Uni- Psychiatry and Neuropsychology, Maastricht University, and Centre for versity at Buffalo, The State University of New York; R. Michael Bagby, Epidemiology and Public Health, Health Service and Population Research Departments of Psychology and Psychiatry, University of Toronto; Robert Department, Institute of Psychiatry, Psychology, and Neuroscience, King’s This document is copyrighted by the American Psychological Association or one of its alliedF. publishers. Krueger, Department of Psychology, University of Minnesota; Jennifer College London; Alexander J. Shackman, Department of Psychology, This article is intended solely for the personal use ofL. the individual user andCallahan, is not to be disseminated broadly. Department of Psychology, University of North Texas; Mi- University of Maryland; Monika A. Waszczuk, Department of Psychiatry, chael Chmielewski, Department of Psychology, Southern Methodist Uni- Stony Brook University; David Watson, Department of Psychology, Uni- versity; Christopher C. Conway, Department of Psychological Sciences, versity of Notre Dame; Aidan G. C. Wright, Department of Psychology, College of William and Mary; Barbara De Clercq, Department of Devel- University of Pittsburgh; Johannes Zimmermann, Department of Psychol- opmental, Personality, and Social Psychology, Ghent University; Allison ogy, University of Kassel. Dornbach-Bender, Department of Psychology, University of North Texas; This article was organized by members of the HiTOP Consortium, a Nicholas R. Eaton, Department of Psychology, Stony Brook University; grassroots organization open to all qualified investigators (https://medicine Miriam K. Forbes, Centre for Emotional Health, Department of Psychol- .stonybrookmedicine.edu/HITOP). Alexander J. Shackman was supported ogy, Macquarie University; Kelsie T. Forbush, Department of Psychology, by the National Institutes of Health (DA040717 and MH107444) and the University of Kansas; John D. Haltigan, Department of Psychiatry, Uni- University of Maryland. Authors 15 through 33 are listed alphabetically by versity of Toronto; Joshua D. Miller, Department of Psychology, Univer- last name. sity of Georgia; Leslie C. Morey, Department of Psychology, Texas A&M Correspondence concerning this article should be addressed to University; Praveetha Patalay, Centre for Longitudinal Studies and MRC Camilo J. Ruggero, Department of Psychology, University of North Unit for Lifelong Health and Ageing, University College London; Darrel Texas, 1155 Union Circle, 311280, Denton, TX 76203-5017. E-mail: A. Regier, Department of Psychiatry, Center for the Study of Traumatic [email protected] INTEGRATING HITOP INTO CLINICAL PRACTICE 1071 A reliable, valid, and clinically useful classification system for used diagnosis is “other specified/unspecified” (“not otherwise mental illness is a cornerstone of clinical practice in the ideal specified” in previous editions of the DSM; Machado, Machado, (Kendell & Jablensky, 2003; Krueger et al., 2018; Mullins-Sweatt Gonçalves, & Hoek, 2007; Verheul & Widiger, 2004), meaning & Widiger, 2009). It facilitates communication, orients and guides the patient’s presentation does not fit any specific category. More- treatment planning, and serves as a common basis for administer- over, the DSM and ICD categories provide little diagnosis-specific ing care. It also can provide information about the natural course information to guide treatment decisions (First et al., 2018). Most of illness against which to measure the effectiveness of treatment categories have a wide range of applicable treatments, with many and create a foundation for research (American Psychiatric Asso- pharmaceutical and psychosocial treatments showing transdiag- ciation, 2006, 2013; First et al., 2014). The present work briefly nostic effects (Barlow, Sauer-Zavala, Carl, Bullis, & Ellard, 2013; reviews limitations of the prevailing nosology in place for most Weitz, Kleiboer, van Straten, & Cuijpers, 2018). Indeed, a driving clinicians. It introduces a new model of nosology spearheaded by force for assigning a patient a DSM or ICD diagnosis may often be quantitative nosologists (Kotov et al., 2017). Prior work has artic- less about clinical care and more about administrative or reim- ulated the empirical basis for these newer models and made clear bursement requirements (Braun & Cox, 2005; Eriksen & Kress, evidence to support its major contours. However, no work has 2004;