Discrete Diagnostic Categories Research Articles

Recent Advances in Group-Based Trajectory Modeling for Clinical Research.

Group-based trajectory modeling (GBTM) identifies groups of individuals following similar trajectories of one or more repeated measures. The categorical nature of GBTM is particularly well suited to clinical psychology and medicine, where patients are often classified into discrete diagnostic categories. This review highlights recent advances in GBTM and key capabilities that remain underappreciated in clinical research. These include accounting for nonrandom subject attrition, joint trajectory and multitrajectory modeling, the addition of the beta distribution to modeling options, associating trajectories with future outcomes, and estimating the probability of future outcomes. Also discussed is an approach to selecting the number of trajectory groups. Expected final online publication date for the Annual Review of Clinical Psychology, Volume 20 is May 2024. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Special Report: Bipolar Disorder II—Frequently Neglected, Misdiagnosed

Special Report: Bipolar Disorder II—Frequently Neglected, Misdiagnosed

Atypical Functional Network Properties and Associated Dimensions of Child Psychopathology During Rest and Task Performance

BackgroundWhen brain networks deviate from typical development, this is thought to contribute to varying forms of psychopathology. However, research has been limited by the reliance on discrete diagnostic categories that overlook the potential for psychological comorbidity and the dimensional nature of symptoms. MethodsThis study examined the topology of functional networks in association with 4 bifactor-defined psychopathology dimensions—general psychopathology, internalizing symptoms, conduct problems, and attention-deficit/hyperactivity disorder symptoms—via the Child Behavior Checklist in a sample of 3568 children from the ABCD (Adolescent Brain Cognitive Development) Study. Local and global graph theory metrics were calculated at rest and during tasks of reward processing, inhibition, and working memory. ResultsGreater attention-deficit/hyperactivity disorder symptoms were associated with reduced modularity across rest and tasks as well as reduced local efficiency in motor networks at rest. Results survived sensitivity analyses for medication and socioeconomic status. Greater conduct problem symptoms were associated with reduced modularity on working memory and reward processing tasks; however, these results did not persist after sensitivity analyses. General psychopathology and internalizing symptoms showed no significant network associations. ConclusionsOur findings suggest reduced efficiency in topology in those with greater attention-deficit/hyperactivity disorder symptoms across 4 critical cognitive states, with conduct problems also showing network deficits, although less consistently. This may suggest that modularity deficits are a neurobiological marker of externalizing behavior in children. Such specificity has not been demonstrated before using graph theory metrics and has the potential to redefine our understanding of network deficits in children with psychopathology symptoms.

Using a Transdiagnostic Perspective to Disrupt White Supremacist Applications of the DSM

White supremacist applications of the Diagnostic and Statistical Manual of Mental Disorders (DSM) result in the disproportionate labeling of Black, Indigenous, and People of Color as violent or severely mentally ill. Racial diagnostic disparities and misdiagnoses are endemic in social work practice, in part because of the DSM’s categorical classification system, which encourages reductive thinking and reinforces implicit racial biases. While courses on psychopathology are common requirements for clinical field placements, the mental health field’s reliance on the DSM often contradicts antiracist curricula. In an effort to address this paradox, we utilize pedagogical approaches that seek to critique and deconstruct White Supremacist applications of the DSM while simultaneously preparing students to enter a field that relies so heavily on diagnostic labels. This is done in part by teaching students to shirk the DSM’s categorical perspective in favor of a transdiagnostic perspective—identifying symptoms or traits underlying human suffering that occur across diagnostic categories and are informed by macro systems of privilege and oppression. Teaching students to adopt a transdiagnostic perspective may disrupt White Supremacist practices in diagnostics by encouraging an acknowledgement of multisystem factors underlying human suffering without relying on discrete diagnostic categories that are prone to racial interpretations.

Blood pressure thresholds in pregnancy for identifying maternal and infant risk: a secondary analysis of Community-Level Interventions for Pre-eclampsia (CLIP) trial data

SummaryBackgroundBlood pressure measurement is a marker of antenatal care quality. In well resourced settings, lower blood pressure cutoffs for hypertension are associated with adverse pregnancy outcomes. We aimed to study the associations between blood pressure thresholds and adverse outcomes and the diagnostic test properties of these blood pressure cutoffs in low-resource settings.MethodsWe did a secondary analysis of data from 22 intervention clusters in the Community-Level Interventions for Pre-eclampsia (CLIP) cluster randomised trials (NCT01911494) in India (n=6), Mozambique (n=6), and Pakistan (n=10). We included pregnant women aged 15–49 years (12–49 years in Mozambique), identified in their community by trained community health workers, who had data on blood pressure measurements and outcomes. The trial was unmasked. Maximum blood pressure was categorised as: normal blood pressure (systolic blood pressure [sBP] <120 mm Hg and diastolic blood pressure [dBP] <80 mm Hg), elevated blood pressure (sBP 120–129 mm Hg and dBP <80 mm Hg), stage 1 hypertension (sBP 130–139 mm Hg or dBP 80–89 mm Hg, or both), non-severe stage 2 hypertension (sBP 140–159 mm Hg or dBP 90–109 mm Hg, or both), or severe stage 2 hypertension (sBP ≥160 mm Hg or dBP ≥110 mm Hg, or both). We classified women according to the maximum blood pressure category reached across all visits for the primary analyses. The primary outcome was a maternal, fetal, or neonatal mortality or morbidity composite. We estimated dose-response relationships between blood pressure category and adverse outcomes, as well as diagnostic test properties.FindingsBetween Nov 1, 2014, and Feb 28, 2017, 21 069 women (6067 in India, 4163 in Mozambique, and 10 839 in Pakistan) contributed 103 679 blood pressure measurements across the three CLIP trials. Only women with non-severe or severe stage 2 hypertension, as discrete diagnostic categories, experienced more adverse outcomes than women with normal blood pressure (risk ratios 1·29–5·88). Using blood pressure categories as diagnostic thresholds (women with blood pressure within the category or any higher category vs those with blood pressure in any lower category), dose-response relationships were observed between increasing thresholds and adverse outcomes, but likelihood ratios were informative only for severe stage 2 hypertension and maternal CNS events (likelihood ratio 6·36 [95% CI 3·65–11·07]) and perinatal death (5·07 [3·64–7·07]), particularly stillbirth (8·53 [5·63–12·92]).InterpretationIn low-resource settings, neither elevated blood pressure nor stage 1 hypertension were associated with maternal, fetal, or neonatal mortality or morbidity adverse composite outcomes. Only the threshold for severe stage 2 hypertension met diagnostic test performance standards. Current diagnostic thresholds for hypertension in pregnancy should be retained.FundingUniversity of British Columbia, the Bill & Melinda Gates Foundation.

Evaluación fenotípica del Trastorno por Déficit de Atención e Hiperactividad (TDAH): existencia de un continuo de gravedad en niños

Background: Within the study of the structure of ADHD there is an ongoing debate as to whether phenotypic differences are due to differences in the severity of symptoms of inattention, hyperactivity, and impulsivity along an underlying continuum or whether the differences reflect are qualitatively distinct subtypes with unique etiologies. Objective: To analyze whether the behaviors of inattention, hyperactivity and impulsivity in children reflect qualitatively different presentations within ADHD, variations along a single continuum of severity or different levels of severity within the representations. Method: A study was carried out through confirmatory factor analysis (CFA), latent class analysis (LCA) and factor mixture models (FMM) of the ADHD phenotype according to the data collected through the Child and Adolescent Behavior Inventory (CABI) of 632 participants (M = 10.46 years; SD = 2.35) from the city of Talca (Chile) in general population. Results: For the 16 models analyzed, it was inferred that the MFM of three factors (IN, HI and IM) and four classes, a majority with a low score (unaffected) and a minority with a high score (affected), with two very similar intermediate categories, showed the best fit. Conclusions: The FMM showed that ADHD would vary along a continuum of severity, within symptoms of the disorder from mild, to moderate, or severe, rather than existing as discrete diagnostic categories.

Risk profiles for mental disorders

Abstract BodyPrognostication is at the bedrock of clinical practice. In essence, diagnosis aims to inform clinicians for decision-making processes by providing a picture of future events such as course, outcome, and treatment response. To make a better clinical prediction on a case-by-case basis, diagnosis is enriched by individual characteristics and (bio)markers, with the aims of stratifying patients first and ultimately reaching the mountaintop: personalized medicine. However, there are two major obstacles on the road to personalized psychiatry. First, the current psychiatric diagnostic classification system is inadequate for tailoring individualized management plan, let alone for guiding the clinician for diagnosis-specific treatment selection—such that response to the same treatment plan largely varies among patients with the same psychiatric diagnosis, whereas patients with different psychiatric diagnoses benefit similarly from the same treatment protocol. Second, except for a few tests for ruling out other medical conditions, there exists no diagnostic, prognostic, or predictive (bio)marker in psychiatry. Risk profiling is even a more challenging and ambitious goal as early psychopathology is multidimensional, fluid, and pluripotent with heterotypic outcomes that cut across traditional diagnostic boundaries. By acknowledging this complexity and the shortcomings of current taxonomy, the field has recently shifted from risk profiling frameworks that rely on discrete diagnostic categories in isolation for prognostication (i.e. clinical high-risk for psychosis) to transdiagnostic clinical staging models. In this session, I will attempt to discuss where we are at with risk profiling in psychiatry and what steps need to be taken to achieve this ambitious goal.DisclosureNo significant relationships.

Hierarchical models of psychopathology: empirical support, implications, and remaining issues.

There is an ongoing revolution in psychology and psychiatry that will likely change how we conceptualize, study and treat psychological problems.- Many theorists now support viewing psychopathology as consisting of continuous dimensions rather than discrete diagnostic categories. Indeed, recent papers have proposed comprehensive taxonomies of psychopathology dimensions to replace the DSM and ICD taxonomies of categories. The proposed dimensional taxonomies, which portray psychopathology as hierarchically organized correlated dimensions, are now well supported at phenotypic levels. Multiple studies show that both a general factor of psychopathology at the top of the hierarchy and specific factors at lower levels predict different functional outcomes. Our analyses of data on a large representative sample of child and adolescent twins suggested the causal hypothesis that phenotypic correlations among dimensions of psychopathology are the result of many familial influences being pleiotropic. That is, most genetic variants and shared environmental factors are hypothesized to non-specifically influence risk for multiple rather than individual dimensions of psychopathology. In contrast, person-specific experiences tend to be related to individual dimensions. This hierarchical causal hypothesis has been supported by both large-scale family and molecular genetic studies. Current research focuses on three issues. First, the field has not settled on a preferred statistical model for studying the hierarchy of causes and phenotypes. Second, in spite of encouraging progress, the neurobiological correlates of the hierarchy of dimensions of psychopathology are only partially described. Third, although there are potentially important clinical implications of the hierarchical model, insufficient research has been conducted to date torec-ommend evidence-based clinical practices.

Deficit schizophrenia is a discrete diagnostic category defined by neuro-immune and neurocognitive features: results of supervised machine learning.

Deficit schizophrenia is characterized by neurocognitive impairments and changes in the patterning of IgA/IgM responses to plasma tryptophan catabolites (TRYCATs). In the current study, supervised pattern recognition methods, including logistic regression analysis (LRA), Support Vector Machine (SVM), and Soft Independent Modeling of Class Analogy (SIMCA), were used to examine whether deficit schizophrenia is a discrete diagnostic class with respect to Consortium To Establish a Registry for Alzheimer's disease (CERAD) and Cambridge Neuropsychological Test Automated Battery (CANTAB) tests and IgA/IgM responses to noxious (NOX) and generally more protective (PRO) TRYCATs. We recruited patients with (n = 40) and without (n = 40) deficit schizophrenia and healthy volunteers (n = 40). The combined use of TRYCAT and CERAD features strongly segregates deficit from nondeficit schizophrenia and healthy controls. Three out of the top five most important features in LRA, SVM and SIMCA agreed, namely two different NOX/PRO TRYCAT ratios and false memory recall. SIMCA shows that deficit schizophrenia is significantly separated from nondeficit schizophrenia and controls with as top 6 features IgA responses to picolinic acid, IgM responses to 3-OH-kynurenine and kynurenic acid, and impairments in Word List Memory and Verbal Fluency Tests and Mini-Mental State Examination. Nevertheless, nondeficit schizophrenia was not significantly separated from controls. The results show that schizophrenia is not a unitary disease with mere continuous differences in severity of illness between apparent subtypes. Deficit schizophrenia is a qualitatively distinct class defined by neuroimmune (autoimmune responses to TRYCATs) and neurocognitive (episodic and semantic memory) features coupled or not with clinical (negative) symptoms.

Beyond comorbidity: Toward a dimensional and hierarchical approach to understanding psychopathology across the life span

We propose a novel developmentally informed framework to push research beyond a focus on comorbidity between discrete diagnostic categories and to move toward research based on the well-validated dimensional and hierarchical structure of psychopathology. For example, a large body of research speaks to the validity and utility of the internalizing and externalizing spectra as organizing constructs for research on common forms of psychopathology. The internalizing and externalizing spectra act as powerful explanatory variables that channel the psychopathological effects of genetic and environmental risk factors, predict adaptive functioning, and account for the likelihood of disorder-level manifestations of psychopathology. As such, our proposed theoretical framework uses the internalizing and externalizing spectra as central constructs to guide future psychopathology research across the life span. The framework is particularly flexible, because any of the facets or factors from the dimensional and hierarchical structure of psychopathology can form the focus of research. We describe the utility and strengths of this framework for developmental psychopathology in particular and explore avenues for future research.

Psychological functioning of people living with chronic pain: a meta-analytic review.

Chronic pain (CP; >3 months) is a common condition that is associated with significant psychological problems. Many people with CP do not fit into discrete diagnostic categories, limiting the applicability of research that is specific to a particular pain diagnosis. This meta-analysis synthesized the large extant literature from a general CP, rather than diagnosis-specific, perspective to systematically identify and compare the psychological problems most commonly associated with CP. Four databases were searched from inception to December 2013 (PsychINFO, The Cochrane Library, Scopus, and PubMed) for studies comparing the psychological functioning of adults with CP to healthy controls. Data from 110 studies were meta-analysed and Cohen's d effect sizes calculated. The CP group reported experiencing significant problems in a range of psychological domains (depression, anxiety, somatization, anger/hostility, self-efficacy, self-esteem and general emotional functioning), with the largest effects observed for pain anxiety/concern and somatization; followed by anxiety and self-efficacy; and then depression, anger/hostility, self-esteem and general emotional functioning. This study demonstrates, for the first time, that individuals with CP are more likely to experience physically focussed psychological problems than other psychological problems and that, unlike self-efficacy, fear of pain is intrinsically tied to the CP experience. This challenges the prevailing view that, for individuals with CP, problems with depression are either equal to, or greater than, problems with anxiety, thereby providing important information to guide therapeutic targets. Positive clinical implications: This is the first time that the CP literature has been synthesized from a general perspective to examine psychological functioning in the presence of CP and provide practical recommendations for assessment and therapy. Individuals with CP were most likely to experience psychological problems in physically focussed areas - namely pain anxiety/concern and somatization. Although fear of pain was intrinsically tied to the CP experience, self-efficacy was not. CP was more strongly associated with anxiety than with depression. Limitations The study focuses on the general CP literature, adults and research-utilizing self-report measures. Meta-analyses are limited by the empirical literature on which they are based.

Depression in Japan: Psychiatric Cures for a Society in Distress (review)

Kalman Applbaum University of Wisconsin-Milwaukee Junko Kitanaka, Depression in Japan: Psychiatric Cures for a Society in Distress. Princeton: Princeton University Press, 2012. 264 pp. Over the past few decades, mainstream psychiatry has re-invented itself as part of modern scientific medicine. It regards mental illness as a brain dysfunction, classified into discrete diagnostic categories, and treatable by pharmaceuticals. Whether by professional design, administrative convenience, popular appeal, or commercial stratagem, this paradigm of practice has come to overshadow psychosocial models in much or most of the world. The history of psychiatry has been told mainly from the point of view of North America and Western Europe, from whence the biological paradigm and the major engines of its dissemination-the DSM (Diagnostic and Statistical Manual of Mental Disorders) and psychopharmaceuticals- originate. Diagnostic and therapeutic traditions that traveled earlier in the 20th century, such as Freudian or Lacanian psychoanalysis, were also Western in origin. With some notable exceptions, most of the attention paid to non-Western healthcare settings has focused on how these places have adapted western neuropsychiatric theories and technologies, often in combination with local ethnopsychiatric traditions. There is good reason to consider Japan over the course of the past roughly 120 years as a unique case in which the national psychiatry is simultaneously in dialogue with developments in the West and yet resolutely an agent and artifact of its own history. Just as economic theorists have delineated operatively familiar and yet distinctive features in Japanese capitalism, one might regard Japanese psychiatry as a fully realized version of the Western-originated discipline but with academic, institutional, and cultural contours of a very different cast. Until lately, anthropologists working in Japan have revealed aspects of Japanese psychiatry only indirectly, which is to say they have not taken professional psychiatry itself as their object of study.1 Junko Kitanaka's Depression in Japan is, in this respect and others I will reflect upon below, a pioneering study in the medical anthropology of Japan. The book takes as its joint objects Japanese psychiatry as an academic discipline and a field of clinical practice on the one hand, and the general footing for mental illness in Japanese society on the other. Although ambitious to the point of sometimes eliciting acrophobia, this double undertaking is essential. It is because the proper historiography and ethnography of modern mental illness demands recognition of its coconstruction at the interface between psychiatry and the public, including individual patients and their families, the courts, the Ministry of Health, Labor, and Welfare (or its equivalent), corporations, and vox populi. The reliable overview of the Japanese psy-complex also fills a missing piece in what might be conceived of as a series of interlocking regional puzzles. It would be false to only slowly unveil my enthusiasm for the result of Kitanaka's investigation. Depression in Japan will be a breakthrough book for cross-cultural psychiatry, medical anthropology, and Japanese studies. By apparent design the book answers many questions that have heretofore puzzled outside observers of mental illness and its treatment in Japan. These include the ambiguous psychiatric classification of suicide in a culture where it has oftbeen romanticized; the higher incidence of depression among men, when in most places the reverse is observed; the entrenchment of neurobiological and inheritance theories of mental illness in a society otherwise famous for its endless public debates on sociallyborne pathologies; the post-war trends of rising institutionalization and the stigmatization of the mentally ill while overlooking common mental disorders, when precisely the opposite was transpiring in the West; and the curious phenomenon of death from overwork. …

FC28-05 - Prevalence of psychiatric diagnoses and challenging behaviours in a community based population of individuals with intellectual disability

IntroductionPrevious research has suggested substantial variation in prevalence rates of psychiatric disorders in individuals with intellectual disability and also differential patterns of associations between psychiatric disorders and challenging behaviours in people with intellectual disabilities. The aim of this study was to determine with the prevalence rate of specific psychiatric disorders and challenging behaviours and the relationship between them in a community based sample of individuals with intellectual disability.MethodA community based sample of 159 adults primarily with mild and moderate intellectual disabilities was surveyed for the presence of psychiatric disorders and challenging behaviour using the Behaviour Problem Inventory (BPI) and the Psychiatric Assessment Schedule (PAS-ADD). Individuals who met threshold on the PAS-ADD were subsequently evaluated using the Mini- PAS-ADD Interview.ResultsScreening for psychiatric disorder using the PAS-ADD indicated a prevalence rate of 10%. There was a large discrepancy between the overall rate of challenging behaviour (45%) and the rate of psychiatric disorders identified by the Mini PAS-ADD Interview (6%). However, the rate of more severe behaviour problems (8%) was closer to the rate of psychiatric disorders (6%). Thirty one percent of people with severe challenging behaviours also were rated as having psychiatric disorders and odd ratio analysis indicates that individuals with severe challenging behaviour are substantially more likely to present with a psychiatric disorder. However, there does not appear to be a relationship between different topographies of challenging behaviour and discrete diagnostic categories of psychiatric disorder.

Prevalence of Psychiatric Diagnoses and Challenging Behaviors in a Community-Based Population of Adults With Intellectual Disability

Previous research has suggested substantial variation in prevalence rates of psychiatric disorders in individuals with intellectual disability (ID) and also differential patterns of associations between psychiatric disorders and challenging behaviors in people with ID. The aim of this study was to determine the prevalence rate of specific psychiatric disorders and challenging behaviors and the relationship between them in a community-based sample of individuals with ID. A community-based sample of 159 adults primarily with mild and moderate ID was surveyed for the presence of psychiatric disorders and challenging behaviors using the Behavior Problem Inventory and the Psychiatric Assessment Schedule (PAS-ADD). Individuals who met threshold on the PAS-ADD were subsequently evaluated using the Mini PAS-ADD Interview. Screening for psychiatric disorders using the PAS-ADD indicated a prevalence rate of 10%. There was a large discrepancy between the overall rate of challenging behaviors (45%) and the rate of psychiatric disorders identified by the Mini PAS-ADD Interview (6%). However, the rate of more severe behavior problems (8%) was closer to the rate of psychiatric disorders (6%). Thirty-one percent of people with severe challenging behaviors also were rated as having psychiatric disorders and odd ratio analysis indicates that individuals with severe challenging behaviors are substantially more likely to present with a psychiatric disorder. However, the relationship between different topographies of challenging behaviors and discrete diagnostic categories of psychiatric disorders appears to be unclear. This study reports a low prevalence of psychiatric disorders in a community-based population. The presence of severe challenging behaviors appears to have some association with psychiatric disorders but does not appear specific to discrete diagnostic categories. Clinicians and researchers need to debate the validity of considering challenging behaviors atypical manifestations of psychiatric disorders.

Kiyang-yang, a West-African Postwar Idiom of Distress

In 1984, a healing cult for young barren women in southern Guinea Bissau developed into a movement, Kiyang-yang, that shook society to its foundations and had national repercussions. “Idiom of distress” is used here as a heuristic tool to understand how Kiyang-yang was able to link war and post-war-related traumatic stress and suffering on both individual and group levels. An individual experience born from a traumatic origin may be generalized into an idiom that diverse sectors of society could embrace for a range of related reasons. We argue that, for an idiom to be understood and appropriated by others, there has to be resonance at the level of symbolic language and shared experiences as well as at the level of the culturally mediated contingent emotions it communicates. We also argue that through its symbolic references to structural causes of suffering, an idiom of distress entails a danger for those in power. It can continue to exist only if its etiology is not exposed or the social suffering it articulates is not eliminated. We finally argue that idioms of distress are not to be understood as discrete diagnostic categories or as monodimensional expressions of “trauma” that can be addressed.

Genetic Control of Human Brain Transcript Expression in Alzheimer Disease

We recently surveyed the relationship between the human brain transcriptome and genome in a series of neuropathologically normal postmortem samples. We have now analyzed additional samples with a confirmed pathologic diagnosis of late-onset Alzheimer disease (LOAD; final n = 188 controls, 176 cases). Nine percent of the cortical transcripts that we analyzed had expression profiles correlated with their genotypes in the combined cohort, and approximately 5% of transcripts had SNP-transcript relationships that could distinguish LOAD samples. Two of these transcripts have been previously implicated in LOAD candidate-gene SNP-expression screens. This study shows how the relationship between common inherited genetic variants and brain transcript expression can be used in the study of human brain disorders. We suggest that studying the transcriptome as a quantitative endo-phenotype has greater power for discovering risk SNPs influencing expression than the use of discrete diagnostic categories such as presence or absence of disease.

Is the Metabolic Syndrome a Discrete Diagnostic Category or the End of a Continuum? Taxometric Evidence for Dimensionality in the National Health and Nutrition Examination Survey 1999–2004

To determine whether the metabolic syndrome is a discrete diagnostic category or the end of a continuum. The study sample consisted of 3959 individuals from the National Health and Nutrition Examination Survey 1999-2004. The taxometric methods of mean above minus mean below a cut (MAMBAC) and maximum covariance (MAXCOV) were used. The primary numerical outcome was the comparative curve fit index (CCFI). For men, the CCFI from MAMBAC and MAXCOV analyses were 0.290 and 0.260, respectively. Likewise, for women, the CCFI from MAMBAC and MAXCOV analyses were 0.317 and 0.311, respectively. The results indicate that the metabolic syndrome is continuously distributed in nature, rather than a discrete diagnostic category.

Taxometric Investigation of PTSD: Data From Two Nationally Representative Samples

Current psychiatric nosology depicts posttraumatic stress disorder (PTSD) as a discrete diagnostic category. However, only one study has examined the latent structure of PTSD, and this study suggested that PTSD may be more accurately conceptualized as an extreme reaction to traumatic life events rather than a discrete clinical syndrome. To build on the existing literature base, the present research examined the latent structure of posttraumatic stress reactions by applying three taxometric procedures (MAXEIG, MAMBAC, and L-Mode) to data collected from large nationally representative samples of women ( ns = 2684 and 3033) and adolescents ( n = 3775). Results consistently provided evidence for a dimensional PTSD solution across samples and statistical procedures. These findings have important implications for the theory, assessment, and investigation of posttraumatic stress reactions.

Therapy of somatoform disorders

Somatoform disorders are categorized in the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR) under the following categories: Somatization Disorder, Undifferentiated Somatoform Disorder, Conversion Disorder, Pain Disorder, Hypochondriasis, Body Dysmorphic Disorder and Somatoform Disorder Not Otherwise Specified (NOS). As a group they are characterized by the presence of physical symptoms that suggest a general medical condition and they must cause clinically significant distress or impairment of social, occupational or other areas of functioning. Evidence suggests that somatoform symptoms account for a significant percentage of primary care consultations. However, their inclusion in DSM-IV-TR as a discrete diagnostic category is controversial. This may explain the small number of treatment studies conducted in the majority of categories of the somatoform disorders. The definition of populations for research studies remains a challenge, as do valid response criteria, because of the heterogeneous populations of subjects with varying co-morbid disorders. As a result, there are very few validated assessment scales. The notable exception to the poorly researched categories is body dysmorphic disorder. Mainly as a result of studies conducted within the Body Dysmorphic Disorder and Body Image Program based in Rhode Island, USA, we now have a better understanding of the disorder and evidence for the efficacy of selective serotonin reuptake inhibitors (SSRIs) in its treatment.

Promising Prospects forDSM-V

Promising Prospects for<i>DSM-V</i>