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Childhood trauma (CT) is associated with an increased risk of mental health disorders; however, it is unknown whether this represents a diagnosis-specific risk factor for specific psychopathology mediated by structural brain changes. Our aim was to explore whether (i) a predictive CT pattern for transdiagnostic psychopathology exists, and whether (ii) CT can differentiate between distinct diagnosis-dependent psychopathology. Furthermore, we aimed to identify the association between CT, psychopathology and brain structure.
We used multivariate pattern analysis in data from 643 participants of the Personalised Prognostic Tools for Early Psychosis Management study (PRONIA), including healthy controls (HC), recent onset psychosis (ROP), recent onset depression (ROD), and patients clinically at high-risk for psychosis (CHR). Participants completed structured interviews and self-report measures including the Childhood Trauma Questionnaire, SCID diagnostic interview, BDI-II, PANSS, Schizophrenia Proneness Instrument, Structured Interview for Prodromal Symptoms and structural MRI, analyzed by voxel-based morphometry.
(i) Patients and HC could be distinguished by their CT pattern with a reasonable precision [balanced accuracy of 71.2% (sensitivity = 72.1%, specificity = 70.4%, p ≤ 0.001]. (ii) Subdomains ‘emotional neglect’ and ‘emotional abuse’ were most predictive for CHR and ROP, while in ROD ‘physical abuse’ and ‘sexual abuse’ were most important. The CT pattern was significantly associated with the severity of depressive symptoms in ROD, ROP, and CHR, as well as with the PANSS total and negative domain scores in the CHR patients. No associations between group-separating CT patterns and brain structure were found.
These results indicate that CT poses a transdiagnostic risk factor for mental health disorders, possibly related to depressive symptoms. While differences in the quality of CT exposure exist, diagnostic differentiation was not possible suggesting a multi-factorial pathogenesis.
The current study aimed to investigate availability and placement of healthy and discretionary (less healthy) food in supermarkets in Victoria, Australia, and examine variation by supermarket chain and area-level socio-economic disadvantage.
Cross-sectional supermarket audit. Measures included: (i) proportion of shelf space (in square metres) allocated to selected healthy and discretionary food and beverages; (ii) proportion of end-of-aisle, checkout and island bin displays containing discretionary food and beverages and (iii) proportion of space within end-of-aisle, checkout and island bin displays devoted to discretionary food and beverages.
Metropolitan areas of Melbourne and Geelong, Australia. Assessment: June–July 2019.
Random sample of 104 stores, with equal numbers from each supermarket group (Coles, Woolworths, Aldi and Independent stores) within strata of area-level socio-economic position.
Proportion of shelf space devoted to selected discretionary foods was greater for Independent stores (72·7 %) compared with Woolworths (65·7 %), Coles (64·8 %) and Aldi (63·2 %) (all P < 0·001). Proportion of shelf space devoted to selected discretionary food for all Coles, Woolworths and Aldi stores was 9·7 % higher in the most compared with the least disadvantaged areas (P = 0·002). Across all stores, 90 % of staff-assisted checkout displays and 50 % of end-of-aisle displays included discretionary food. Aldi was less likely to feature discretionary food in end-of-aisle and checkout displays compared with other supermarket groups.
Extensive marketing of discretionary food in all Australian supermarket chains was observed, which is likely to strongly influence purchasing patterns and population diets. Findings should be used to inform private and public sector policies to reduce marketing of discretionary food in supermarkets.
Prevention of severe mental disorders, and especially the indicated prevention, has become a main topic in psychiatric research and, consequently, a matter of ethical debates. Neuropsychiatric disorders, however, form a most heterogeneous group of disorders that, among others, strike first in different age groups, differ in outcome and in availability as well as safety of treatments, have more or less understood different aetiologies and are subject to different degrees of stigmatisation and discrimination. And, although the main focus and critic are on the accuracy of prediction and the safety of treatment, concerns and arguments vary with the different characteristics of the considered disorder.
Taking endogenous psychoses as an example, costs and benefits of an early detection, of an early intervention and of prevention research in the prodromal or premorbid phase will be reviewed. It will be argued that the best way to adhere to the major ethical principles in medicine - autonomy, nonmaleficence, beneficence and fairness - in research and clinical practice will have to be reassessed continuously against the background of the current state of knowledge as well as the public opinion. Thereby, great care has to be given to ensuring that the great expected ‘common good’ will not overcome an individual patient's right to his or her own good and that, especially in patients more vulnerable to misuse, i.e., minors and those already impaired in their decision-making capacity, autonomy is given priority.
This guidance paper from the European Psychiatric Association (EPA) aims to provide evidence-based recommendations on early intervention in clinical high risk (CHR) states of psychosis, assessed according to the EPA guidance on early detection. The recommendations were derived from a meta-analysis of current empirical evidence on the efficacy of psychological and pharmacological interventions in CHR samples. Eligible studies had to investigate conversion rate and/or functioning as a treatment outcome in CHR patients defined by the ultra-high risk and/or basic symptom criteria. Besides analyses on treatment effects on conversion rate and functional outcome, age and type of intervention were examined as potential moderators. Based on data from 15 studies (n = 1394), early intervention generally produced significantly reduced conversion rates at 6- to 48-month follow-up compared to control conditions. However, early intervention failed to achieve significantly greater functional improvements because both early intervention and control conditions produced similar positive effects. With regard to the type of intervention, both psychological and pharmacological interventions produced significant effects on conversion rates, but not on functional outcome relative to the control conditions. Early intervention in youth samples was generally less effective than in predominantly adult samples. Seven evidence-based recommendations for early intervention in CHR samples could have been formulated, although more studies are needed to investigate the specificity of treatment effects and potential age effects in order to tailor interventions to the individual treatment needs and risk status.
Research on at-risk states of psychosis has mainly aimed to predict conversion. Yet as a considerable number of patients does not to progress to this outcome during the investigated observation periods, the course of these non-converters (NC) is of major interest, particularly with regard to preventive interventions and treatment.
To analyze the psychopathological and functional in 18-month non-converters.
Data were derived from the prospective multicenter European Prediction of Psychosis Study with an 18-month follow-up period. Participants had to fulfill ultra-high risk criteria and/or the COGDIS criterion, which is based on a set of cognitive basic symptoms. Psychopathology was assessed with the Structure Interview for Prodromal Syndromes (SIPS), including the Global Assessment of Functioning Scale (GAF) and a short version of the Schizophrenia Proneness Instrument (SPI-A).
All total and subscale scores improved significantly during follow-up. However, a more detailed analysis revealed that a considerable part of the patients showed no improvement or even a worsening of psychopathology and function.
Our first analysis of course on non-converters shows that a high proportion of patients improved. In the light of results from retrospective studies, however, this improvement has to be interpreted with caution, as the observation period does not allow to determine the proportion of outpost syndromes, i.e. precursors of a later prodrome. Furthermore, a considerable portion of our sample worsened functionally and/or symptomatically. With regard to retrospective schizophrenia related results, very long observation periods may be needed to characterize the patterns of course in subpsychotic syndromes.
The aim of this guidance paper of the European Psychiatric Association is to provide evidence-based recommendations on the early detection of a clinical high risk (CHR) for psychosis in patients with mental problems. To this aim, we conducted a meta-analysis of studies reporting on conversion rates to psychosis in non-overlapping samples meeting any at least any one of the main CHR criteria: ultra-high risk (UHR) and/or basic symptoms criteria. Further, effects of potential moderators (different UHR criteria definitions, single UHR criteria and age) on conversion rates were examined. Conversion rates in the identified 42 samples with altogether more than 4000 CHR patients who had mainly been identified by UHR criteria and/or the basic symptom criterion ‘cognitive disturbances’ (COGDIS) showed considerable heterogeneity. While UHR criteria and COGDIS were related to similar conversion rates until 2-year follow-up, conversion rates of COGDIS were significantly higher thereafter. Differences in onset and frequency requirements of symptomatic UHR criteria or in their different consideration of functional decline, substance use and co-morbidity did not seem to impact on conversion rates. The ‘genetic risk and functional decline’ UHR criterion was rarely met and only showed an insignificant pooled sample effect. However, age significantly affected UHR conversion rates with lower rates in children and adolescents. Although more research into potential sources of heterogeneity in conversion rates is needed to facilitate improvement of CHR criteria, six evidence-based recommendations for an early detection of psychosis were developed as a basis for the EPA guidance on early intervention in CHR states.
Surface based MRI methods are a promising approach for the identification of cerebral shape alterations in schizophrenia . In particular, investigating gyrification might offer important evidence for disturbed neurodevelopmental mechanisms in schizophrenia.
The present study is the first to compare on a vertex - wise basis mean curvature as a sensitive parameter for the identification of local gyrification changes in first episode schizophrenia.
54 patients with first-episode schizophrenia and 54 healthy control subjects underwent high-resolution T1-weighted MRI scans. Surface extraction and mean curvature calculation was performed using the Freesurfer Software package. Statistical cortical maps were created to estimate gyrification differences between groups.
A significantly increased gyrification was detected in patients relative to controls in a large right parahippocampal-lingual cortex area. A further analysis of cortical thickness of this cluster revealed concurrent significant reduced cortical thickness in patients.
This is the first study to reveal an aberrant gyrification of the medial surface in first episode schizophrenia on basis of a vertex - wise analysis of local gyrification changes of the entire cortex. Both affected areas, the parahippocampal and the lingual cortex, are of high pathophysiological relevance for schizophrenia. Thus, our data provided new in vivo evidence for an early maturational deficit of these cortical areas in schizophrenia .
The human endocannabinoid system interacts with various neurotransmitter systems and the endocannabinoid anandamide was found significantly elevated in CSF and inversely correlated to psychopathology (Giuffrida et al. 2004) providing a link to the neurobiology of schizophrenia. While delta-9-tetrahydrocannabinol, the psychoactive compound of Cannabis sativa, shows psychedelic properties, the major herbal cannabinoid compound cannabidiol was suggested recently a re-uptake inhibitor of anandamide. In addition potential antipsychotic properties have been hypothezised.
We performed an explorative, 4-week, double-blind, controlled clinical trial on the effects of purified cannabidiol in acute schizophrenia compared to the antipsychotic amisulpride. The antipsychotic properties of both drugs were the primary target of the study. Furthermore, side-effects and anxiolytic capabilities of both treatments were investigated.
42 patients fulfilling DSM-IV criteria of acute paranoid schizophrenia or schizophreniform psychosis participated in the study. Both treatments were associated with a significant decrease of psychotic symptoms after 2 and 4 weeks as assessed by BPRS and PANSS. However, there was no statistical difference between both treatment groups. In contrast, cannabidiol induced significantly less side effects (EPS, increase in prolactin, weight gain) when compared to amisulpride.
Cannabidiol proved substantial antipsychotic properties in acute schizophrenia. This is in line with our suggestion of an adaptive role of the endocannabinoid system in paranoid schizophrenia, and raises further evidence that this adaptive mechanism may represent a valuable target for antipsychotic treatment strategies.
The Stanley Medical Research Institute (00-093 to FML) and the Koeln Fortune Program (107/2000 + 101/2001 to FML) funded this study.
A main objective of EPOS is to provide a valid multifactorial model for the prediction of psychosis. One major element of such a model should be the clinical state.
In a European multicentre study, persons fulfilling clinical criteria thought to indicate an increased risk for psychosis (PAR) were assessed amongst others with different psychopathological instruments covering the whole spectrum from basic symptoms to frank psychotic symptoms. Inclusion criteria comprised attenuated positive symptoms (APS), brief limited intermittent psychotic symptoms (BLIPS), cognitive basic symptoms (CogDis) and a combination of family risk and reduced functioning (S&T).
246 PAR were included into the study, mostly by APS or CogDis. Analysis of demographical data showed a high amount of functional impairment, resulting e.g. in low mean GAF scores (51.0 ± 11.8 SD), and of non-psychotic axis-I disorders. In September 2006, the hazard rate for a conversion to psychosis was 15.3 at 12 and 20.0 at 18 months after baseline assessment. According to the inclusion criteria, the highest rate of conversion was observed among PAR with BLIPS. On a dimensional level, a low GAF score was among the best predictors of conversion.
The transition rates of EPOS were in line with recent studies. A first analysis of clinical data supports the notion that the functional state should be an inherent part of any set of clinical risk criteria. Further analysis will consider the contribution of single symptoms or symptom combinations and the impact of symptom duration.
One aim of the European prediction of psychosis study (EPOS) has been to evaluate the clinical course of putatively prodromal patients in terms of psychopathology.
245 patients at risk for psychosis defined by attenuated positive symptoms, brief limited psychotic symptoms, a state/ trait combination or cognitive-perceptive basic symptoms was recruited in six centres in four countries. The Structured Interview for Prodromal Syndromes (SIPS) and the Bonn Scale for the Assessment of Basic Symptoms – Prediction List (BSABS-P) were employed. Follow-up was scheduled after 9 months (t1) and 18 months.
In total, 40 patients developed a psychosis (P). Compared to those without a transition (NP), P showed significantly higher SIPS scores at baseline. The same applied to the BSABS-P sub-scores 'cognitive perception disturbances' and 'cognitive motor disturbances'. The P sub-group developing psychosis after t1 showed no significant change of the SIPS positive (SIPS-P) sub-score or of any BSABS-P score from baseline to t1, whereas all scores improved in the NP group. At t1, SIPS-P and BSABS-P sub-score 'cognitive thought disturbances' were significantly lower in those later becoming psychotic.
Patients at risk showing a transition to psychosis during exhibited a pronounced psychopathology at baseline. Also, the positive symptom scores did not significantly improve during 1st follow-up, whereas those patients with no transition during the complete follow-up showed an improvement of all scores. As EPOS is a naturalistic study, different treatments have been performed in a considerable portion of the patients and association with course awaits further analysis.
After two decades of research, prevention of psychosis becomes increasingly accepted in clinical psychiatry. However, there are still unmet scientific and clinical needs. Therefore, guidance for prediction as well as prevention is required, reflecting their current capabilities, but also their requirements and limitations.
Evaluating the current state of risk estimation and prevention.
Developing clinical recommendations for the prediction and prevention of psychosis.
42 samples, mainly defined by ultra-high risk criteria and/or the basic symptoms criterion ‘COGDIS‘, were included into meta-analyses of prevention, 15 studies into meta-analyses of prevention.
The pooled conversion rate at >4-year follow-up was 37.0% in UHR and 61.3% in COGDIS samples. The 12-month pooled risk ratio was 0.44, the NNT 10. Psychosocial functioning seemed not to improve, however results were inconclusive due to methodological issues of the trials. Both meta-analyses indicated age related differences.
Several recommendations were developed to guide prediction and prevention, emphasizing age-adapted strategies; details will be presented and discussed during the symposium.
Regarding future steps to further improve prediction and thus prevention, neurocognitive and neurobiological parameters of information processing, i.e. mismatch negativity, P300 and processing speed, as well as support vector machine based analysis of structural MRI seem to be most promising. Furthermore, with regard to current developmental models of psychotic disorders, risk should be conceptualized as dynamically modulated over time and thus presumably non-linearly related to future outcome. Therefore, studies need to consider the fluid interplay of risk and resilience factors to advance prediction significantly.
In patients with schizophrenia, premorbid psychosocial adjustment is an important predictor of functional outcome. We studied functional outcome in young clinical high-risk (CHR) patients and how this was predicted by their childhood to adolescence premorbid adjustment.
In all, 245 young help-seeking CHR patients were assessed with the Premorbid Adjustment Scale, the Structured Interview for Prodromal Syndromes (SIPS) and the Schizophrenia Proneness Instrument (SPI-A). The SIPS assesses positive, negative, disorganised, general symptoms, and the Global Assessment of Functioning (GAF), the SPI-A self-experienced basic symptoms; they were carried out at baseline, at 9-month and 18-month follow-up. Transitions to psychosis were identified. In the hierarchical linear model, associations between premorbid adjustment, background data, symptoms, transitions to psychosis and GAF scores were analysed.
During the 18-month follow-up, GAF scores improved significantly, and the proportion of patients with poor functioning decreased from 74% to 37%. Poor premorbid adjustment, single marital status, poor work status, and symptoms were associated with low baseline GAF scores. Low GAF scores were predicted by poor premorbid adjustment, negative, positive and basic symptoms, and poor baseline work status. The association between premorbid adjustment and follow-up GAF scores remained significant, even when baseline GAF and transition to psychosis were included in the model.
A great majority of help-seeking CHR patients suffer from deficits in their functioning. In CHR patients, premorbid psychosocial adjustment, baseline positive, negative, basic symptoms and poor working/schooling situation predict poor short-term functional outcome. These aspects should be taken into account when acute intervention and long-term rehabilitation for improving outcome in CHR patients are carried out.
The basic symptom criterion 'cognitive disturbances” (COGDIS) and ultra-high risk (UHR) criteria are commonly used for the prediction of psychosis.
However, their predictive value has been assessed so far only by survival analyses using one-time baseline ratings and time-to-conversion. Thereby, potentially risk status-informative fluctuations in risk criteria ratings over time remained unaccounted for.
Therefore we studied if and how the predictive value of COGDIS and the main UHR criterion attenuated psychotic symptoms (APS) and their combination might be influenced by their presence across different assessment times.
In a naturalistic 24-month study, 146 patients at risk for 'cognitive-perceptive basic symptoms” were repeatedly examined (monthly assessments until month 6, thereafter 3-monthly) for COGDIS and APS with the Schizophrenia Proneness Instrument, Adult version, and the Structured Interview of Prodromal Syndromes. Joint latent class analysis was applied to identify different patterns of risk criteria over time and to detect the degree of their association with risk for conversion to psychosis.
The final model included 4 classes: no risk criteria, exclusively BS, exclusively APS and the combination of COGDIS and APS. Class-specific trajectories and survival functions were associated with an increased risk for the conversion to psychosis from a mild to an intense degree, demonstrating a superior performance of the combination of BS and APS.
This result reinforces earlier results of a clearly superior psychosis-predictive value of this combination at baseline and shows that its stability over time. Thus, APS and COGDIS should be repeatedly monitored.
Ultra-high risk (UHR) criteria are defined by attenuated and/or transient full-blown psychotic symptoms and/or a combination of genetic risk factor and deterioration of functioning. To achieve a higher predictive specificity and a clear threshold of clinical importance, functional impairment has been considered as an obligate part of all UHR criteria.
In the European Prediction of Psychosis Study (EPOS)N = 37 participants converted to psychosis, n = 146 completed the whole 18-month follow-up period without conversion. Assessed by the Global Assessment of Functioning Scale, modified version (GAF-M), the following functional states were considered: Considered GAF-M: ≤30%/≤10% reduction of baseline scores related to highest scores in the previous year; scores ≤70/≤60.
The GAF reduction criteria led to a very unfavorable loss of sensitivity, even, if only 10% were demanded. This was accompanied by correspondingly unfavorable accuracy measures. Introducing functional impairment criteria defined by the current state reported to be predictive for psychiatric caseness (score ≤ 70) or to define serious impairment (score ≤ 60) (Kessler et al., 2002, 2003) kept sensitivity at a perfectly high level, yet did not produce any gain of specificity.
These results were certainly be caused by the fact that the whole group showed already low GAF-M scores in the previous year. Thus, a functional impairment criterion proved not to be useful to improve prediction. However, a combination of APS or BLIPS with a ‘clinical status’ criterion of GAF-M ≤ 70 may be considerable to demonstrate a strong need for intervention.
Childhood adversity (CA) is associated with poor mental health outcomes including psychotic symptoms.
However, the mechanisms linking CA to the development of psychosis are still poorly understood – in both their nature and the specificity of links for psychosis development. Possible links (mediators) are an excessive use of external attributions, dysfunctional coping patterns, and depressive symptoms that were associated with CA in healthy subjects but have not been studied in patients at-risk for psychosis.
Therefore, pathways models from CA to depressiveness were generated based on literature and examined separately in two samples by structural equation modeling: 137 patients at-risk for psychosis and 228 help-seeking controls.
Mediators between CA (Trauma and Distress Scale) and depressiveness (BDI II) were attribution style, self-efficacy (Competence and Control Beliefs Questionnaire) and coping strategies (Stress-Coping-Questionnaire).
Both final models showed 3 pathways running from CA to external attributions and low-self-efficacy, from these beliefs to maladaptive coping strategies and from there to depressiveness (CFI>0.9, RMSEA<0.1). In addition, the at-risk group displayed an alternative effect of CA on maladaptive coping.
Our findings suggest that CA generally increases the risk for mental health problems by the development of dysfunctional attributions and low self-efficacy that lead to maladaptive coping strategies and heightened levels of depressiveness with an additional effect of CA on maladaptive coping in at-risk patients. Thus, integrated interventions targeting these factors may enhance resilience and, thereby, prevent both the persistence of distressing symptoms and their progression to mental disorders, including psychosis.
A considerable part of clinical high-risk samples does not convert to psychosis within the studies' limited observation periods. A part of these ‘non-converters’ shows a remission of symptoms (with unknown future course). Another part, however, maintains the risk state during follow-up.
Persistence of indicators for an increased risk of psychosis.
To investigate, if persistence of attenuated (APS) or brief limited intermittent psychotic symptoms (BLIPS), the core syndromes of ultra-high risk (UHR) criteria, can be predicted clinically.
N = 129 participants of the European Prediction of Psychosis (EPOS) Study were included into the current analysis. Persistent Risk Symptoms (pRS) were defined as an at-least ‘moderate’ level (SIPS) of at least one positive symptom at all visits (symptom had to remain the same). Functional significance was defined by a GAF-M score ≤60 at 18-month follow-up (T2).
23.3% displayed persistent risk symptoms throughout follow-up. Most frequent pRS were ‘unusual thought contents’, ‘ideas of persecution’ and ‘perceptual disturbances’. In 90% of the pRS subjects, but only in 25.3% of the non-pRS subjects, GAF scores at T2 were below 60 points (p < 0.01).
Logistic regression analysis revealed that the presence of the pRS syndrome at T2 was predictable by the early course of attenuated positive symptoms with maximum accuracy when the number of at least ‘moderate’ symptoms was considered.
A considerable number of subjects at risk showed persistent attenuated positive symptoms associated with long-lasting functional impairments, irrespective of conversion within the foreseeable future.
The link between depression and paranoia has long been discussed in the psychiatric literature. Because this association is difficult to study in patients with full-blown psychosis, we investigated clinical high-risk (CHR) patients.
To clarify the causal connection between depression and paranoia.
To investigate how clinical depression relates to presence and new occurrence of paranoid symptoms in CHR patients.
Altogether, 245 young help-seeking CHR patients were assessed for suspiciousness/paranoid symptoms with the Structured Interview for Prodromal Syndromes at baseline, 9-month and 18-month follow-up. At baseline, clinical diagnoses were assessed by the Structured Clinical Interview for DSM-IV, childhood stressful experiences by the Trauma and Distress Scale, trait of suspiciousness by the Schizotypal Personality Questionnaire, and anxiety and depressive symptoms by the Positive and Negative Syndrome Scale.
At baseline, 54.3 % of CHR patients reported at least moderate paranoid symptoms. At 9- and 18-month follow-ups, the corresponding figures were 28.3 % and 24.4 %. Depressive disorder, sexual abuse and anxiety symptoms associated with paranoid symptoms. Depressive, obsessive-compulsive and somatoform disorders, sexual abuse, and anxiety predicted occurrence of paranoid symptoms.
Depressive disorder is one of the major clinical factors associating with and predicting paranoid symptoms in CHR patients; also childhood sexual abuse and anxiety symptoms associate with paranoia. In addition, obsessive-compulsive and somatoform disorders seem to predict paranoid symptoms. Low self-esteem may be a common mediator between affective disorders and paranoia. Effective treatment of these disorders may alleviate paranoid symptoms and improve interpersonal functioning in CHR patients.
The ultra-high risk state of developing a psychosis is mainly characterized by attenuated or transient full-blown psychotic symptoms. It can be assessed with the structured interview for prodromal symptoms (SIPS), comprising four domains: positive, negative, disorganization and general symptoms. As the scores of the SOPS sub-domains are regularly used to perform domain-related analyses the stability of the suggested domain structure and item composition is of major interest.
SIPS (version 3.0) data from n = 243 participants of the European Prediction of Psychosis Study (EPOS) were used for the current analysis. Inclusion criteria comprised ultra-high risk criteria and the basic symptom criterion COGDIS. The EPOS investigators received extensive training by one of the scale's authors (Tandy J. Miller, PhD). Pairwise interrater concordance for SIPS was 77%, which was determined acceptable by the training team. A principal component analysis was performed (Eigenvalues > 1, varimax rotation).
A five factor solution emerged. Factor 1 was primarily defined by a loss of intentionality, functioning and stress tolerance, factor 2 by anhedonia and affective blunting, factor 3 by cognitive and behavioural disorganization, factor 4 by delusions. Sleep disturbances and perceptual abnormalities/hallucinations have both been associated with dopaminergic disturbances, this may explain their common appearance on factor 5.
The originally suggested structure of the SIPS proofed not to be stable and was replaced by a five-factor solution. Our results suggest considering a different item and factor structure in future SIPS based data analyses.