The effect of childhood adversity on 4-year outcome in individuals at ultra high risk for psychosis in the Dutch Early Detection Intervention Evaluation (EDIE-NL) Trial.

Childhood adversity is associated with a range of mental disorders, functional impairment and higher health care costs in adulthood. In this study we evaluated if childhood adversity was predictive of adverse clinical and functional outcomes and health care costs in a sample of patients at ultra-high risk (UHR) for developing a psychosis. Structural Equation Modeling was used to examine the effect of childhood adversity on depression, anxiety, transition to psychosis and overall functioning at 4-year follow-up.

The Prodromal Questionnaire: a case for IRT-based adaptive testing of psychotic experiences?

Computerized adaptive tests (CATs) for positive and negative psychotic experiences were developed and tested in N = 5705 help-seeking, non-psychotic young individuals. Instead of presenting all items, CATs choose a varying number of different items during test administration depending on respondents' previous answers, reducing the average number of items while still obtaining accurate person estimates. We assessed the appropriateness of two-parameter logistic models to positive and negative symptoms of the Prodromal Questionnaire (PQ), computed measurement precision of all items and resulting adaptive tests along psychotic dimensions by Real Data Simulations (RDS), and computed indices for criterion and predictive validities of the CATs.

Four-Year Cost-effectiveness of Cognitive Behavior Therapy for Preventing First-episode Psychosis: The Dutch Early Detection Intervention Evaluation (EDIE-NL) Trial.

Background: This study aims to evaluate the long-term cost-effectiveness of add-on cognitive behavior therapy (CBT) for the prevention of psychosis for individuals at ultrahigh risk (UHR) of psychosis.

Method: The Dutch Early Detection and Intervention randomized controlled trial was used, comparing routine care (RC; n = 101) with routine care plus CBT for UHR (here called CBTuhr; n = 95). A cost-effectiveness analysis was conducted with treatment response (defined as proportion of averted transitions to psychosis) as an outcome and a cost-utility analysis with quality-adjusted life years (QALYs) gained as a secondary outcome.

COMT Val(158)Met genotype and cannabis use in people with an At Risk Mental State for psychosis: Exploring Gene x Environment interactions.

Background: Epidemiological and retrospective studies suggest a cannabis x catechol-O-methyltransferase (COMT) Val(158)Met interaction effect on development of psychosis. The aim of this study was to examine this interaction and its association with severity of subclinical symptoms in people with an At Risk Mental State (ARMS) for psychosis.

Methods: Severity of symptoms, cannabis use and genotype were assessed at baseline in 147 help-seeking young adults who met the ARMS criteria and agreed to participate in the Dutch Early Detection and Intervention (EDIE-NL) trial.

Four-Year Follow-up of Cognitive Behavioral Therapy in Persons at Ultra-High Risk for Developing Psychosis: The Dutch Early Detection Intervention Evaluation (EDIE-NL) Trial.

Background: Previously, we demonstrated that cognitive behavior therapy for ultra-high risk (called CBTuhr) halved the incidence of psychosis over an 18-month period. Follow-up data from the same study are used to evaluate the longer-term effects at 4 years post-baseline.

Method: The Dutch Early Detection and Intervention Evaluation study was a randomized controlled trial of 196 UHR patients comparing CBTuhr with treatment-as-usual (TAU) for comorbid disorders with TAU only.

The distribution of self-reported psychotic-like experiences in non-psychotic help-seeking mental health patients in the general population; a factor mixture analysis.

Purpose: Factor mixture analysis (FMA) and item response mixture models in the general population have shown that the psychosis phenotype has four classes. This study attempted to replicate this finding in help-seeking people accessing mental health services for symptoms of non-psychotic mental disorders.

Methods: All patients (18-35 years old) referred for non-psychotic mental health problems to the secondary mental healthcare service in The Hague between February 2008 to February 2010 (N = 3,694), were included.

Depression and social anxiety in help-seeking patients with an ultra-high risk for developing psychosis.

Knowledge on associations between ultra-high risk (UHR) for developing psychosis and on non-psychotic psychopathology in help-seeking populations is limited with respect to differences between male and female patients. The present study tests the hypothesis that both social anxiety and depression are highly prevalent in an UHR population, particularly among women. From February 2008 to February 2010 baseline data were collected from help-seeking subjects (14-35 years) who were included in the Dutch Early Detection and Intervention Evaluation (EDIE-NL) trial.

Cognitive behavioral therapy for subjects at ultrahigh risk for developing psychosis: a randomized controlled clinical trial.

Background: Evidence for the effectiveness of treatments for subjects at ultrahigh risk (UHR) for developing psychosis remains inconclusive.

Objective: A new cognitive behavioral intervention specifically targeted at cognitive biases (ie, Cognitive Behavioral Therapy [CBT] for UHR patients plus treatment as usual [TAU] called CBTuhr) is compared with TAU in a group of young help-seeking UHR subjects.

Methods: A total of 201 patients were recruited at 4 sites and randomized.

The validity of the 16-item version of the Prodromal Questionnaire (PQ-16) to screen for ultra high risk of developing psychosis in the general help-seeking population.

In order to bring about implementation of routine screening for psychosis risk, a brief version of the Prodromal Questionnaire (PQ; Loewy et al., 2005) was developed and tested in a general help-seeking population. We assessed a consecutive patient sample of 3533 young adults who were help-seeking for nonpsychotic disorders at the secondary mental health services in The Hague with the PQ.

Pathways to psychosis: help-seeking behavior in the prodromal phase.

Background: Knowledge of pathways to care by help-seeking patients prior to the onset of psychosis may help to improve the identification of at-risk patients. This study explored the history of help-seeking behavior in secondary mental health care services prior to the onset of the first episode of psychosis.

Method: The psychiatric case register in The Hague was used to identify a cohort of 1753 people in the age range of 18-35 at first contact who developed a psychotic disorder in the period from 1 January 2005 to 31 December 2009.

A single blind randomized controlled trial of cognitive behavioural therapy in a help-seeking population with an At Risk Mental State for psychosis: the Dutch Early Detection and Intervention Evaluation (EDIE-NL) trial.

Background: Psychotic disorders are a serious mental health problem. Intervention before the onset of psychosis might result in delaying the onset, reducing the impact or even preventing the first episode of psychosis. This study explores the effectiveness of cognitive behavioural therapy (CBT) in targeting cognitive biases that are involved in the formation of delusions in persons with an ultra-high risk for developing psychosis.