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.

This article narrates a consensus history of the proposal to include diagnostic criteria for a psychosis risk syndrome in the DSM-5, in part, to document what happened, but also to potentially help focus future efforts at clinically useful early detection. The purpose of diagnosing a risk state would be to slow and ideally prevent the development of the full disorder. Concerns about diagnosing a psychosis risk state included a high false positive rate, potentially harmful use of anti-psychotic medication with people who would not transition to psychosis, and stigmatization. Others argued that educating professionals about what ‘risk’ entails could reduce inappropriate treatments. During the revision, the proposal shifted from diagnosing risk to emphasizing current clinical need associated with attenuated psychotic symptoms. Within the community of researchers who studied psychosis risk, people disagreed about whether risk and/or attenuated symptoms should be an official DSM-5 diagnosis. Once it became clear that the DSM-5 field trials did not include enough cases to establish the reliability of the proposed criteria, everyone agreed that the criteria should be put in a section on conditions for further study rather the main section of the DSM-5. We close with recommendations about some practical benchmarks that should be met for including criteria for early detection in the classification system.

Objective: This study was conducted to describe Axis I sexual diagnoses of 60 males arrested for possession of child pornography obtained via the Internet and/or attempting to meet children via the Internet.

Methods: Data was obtained from a chart review of evaluations conducted on 60 males referred for a psychosexual evaluation following an arrest for possession of child pornography and/or attempting to meet children. All crimes involved use of the Internet. Information obtained from the chart review was entered into SAS. All diagnoses were made according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision. Simple descriptive statistics were computed and cross tabulations were tested for significance using χ2 or Fisher's Exact test.

Results: Of the total sample, 40% had at least one paraphilia. Thirty-one percent had a diagnosis of pedophilia and 18% of a paraphilia not otherwise specified (NOS). Thirty-three percent had a sexual disorder NOS, characterized by hypersexuality. Seventy percent of the total sample had an Axis I disorder that antedated and was judged to be contributory to the behavior leading to their arrest.

Conclusions: This sample of men arrested for committing crimes against children and adolescents via the Internet has a high incidence of lifetime sexual and other psychopathology.

Background. The objective of this paper is to describe and conceptualize an unusual and probably rare condition: the intense longstanding desire to have an amputation.

Method. Structured interviews were conducted by telephone of 52 subjects (mean age: 48·6, range 23–77 years; 47 male, 4 female, 1 intersexed) self-identified as having had a desire to have an amputation.

Results. Seventeen per cent (n=9) had an arm or leg amputated with two-thirds using methods that put the subject at risk of death and one-third enlisting a surgeon to amputate their healthy limb. The most common reported reason for wanting an amputation was the subject's feeling that it would correct a mismatch between the person's anatomy and sense of his or her ‘true’ self (identity). None were delusional. For all but one subject age at onset was during childhood or early adolescence. For those who had psychotherapy or medication there was no change in the intensity of the desire for amputation. The six subjects who had an amputation at their desired site reported that following the amputation they felt better than they ever had and no longer had a desire for an amputation.

Conclusions. These preliminary results suggest the existence of an extremely unusual clinically distinct condition characterized by a lifelong desire to have an amputation of a particular limb. The condition is associated with serious negative consequences: amputation attempts, impairment and marked distress. Reflecting similarities between Gender Identity Disorder and this condition, the author suggests that it may be conceptualized as an unusual dysfunction in the development one's fundamental sense of anatomical (body) identity.

The editorial by Andrews et al (1999) usefully calls attention to issues of compatibility between diagnostic classification systems but we believe that the editorial greatly overstates the compatibility problem as well as its implications. The article begins with the suggestion that the DSM–IV authors' position is to downplay the differences between DSM–IV and ICD–10. After stating that the American Psychiatric Association “felt sufficiently confident to publish a DSM–IV International Version in which the DSM–IV criteria are listed against the ICD–10 codes”, the authors go on to report concordances between the classifications for the main mental disorders as ranging from a low of 33% (for substance harmful use or abuse) to 87% (for dysthymia), with an overall concordance of only 68%. The authors conclude that if this “unnecessary dissonance between the classification systems continues, patients, researchers and clinicians will be all the poorer”. Although we acknowledge that there are a number of differences between the two systems, the authors fail to assess fully the sources, significance and solutions for this compatibility problem.