59 results on '"van der Gaag M"'
Search Results
2. Associations between disturbed sleep and attenuated psychotic experiences in people at clinical high risk for psychosis.
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Formica, M. J. C., Fuller-Tyszkiewicz, M., Reininghaus, U., Kempton, M., Delespaul, P., de Haan, L., Nelson, B., Mikocka-Walus, A., Olive, L., Ruhrmann, S., Rutten, B., Riecher-Rössler, A., Sachs, G., Valmaggia, L., van der Gaag, M., McGuire, P., van Os, J., and Hartmann, J. A.
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SELF-evaluation ,RISK assessment ,MENTAL health ,PREDICTION models ,RESEARCH funding ,QUESTIONNAIRES ,MULTIPLE regression analysis ,INTERVIEWING ,DESCRIPTIVE statistics ,PERCEPTUAL disorders ,SLEEP deprivation ,COGNITION disorders ,RESEARCH methodology ,PSYCHOSES ,COMPARATIVE studies ,DATA analysis software ,SLEEP quality ,SLEEP disorders ,DISEASE complications - Abstract
Background: Pre-diagnostic stages of psychotic illnesses, including 'clinical high risk' (CHR), are marked by sleep disturbances. These sleep disturbances appear to represent a key aspect in the etiology and maintenance of psychotic disorders. We aimed to examine the relationship between self-reported sleep dysfunction and attenuated psychotic symptoms (APS) on a day-to-day basis. Methods: Seventy-six CHR young people completed the Experience Sampling Methodology (ESM) component of the European Union Gene-Environment Interaction Study, collected through PsyMate® devices, prompting sleep and symptom questionnaires 10 times daily for 6 days. Bayesian multilevel mixed linear regression analyses were performed on time-variant ESM data using the brms package in R. We investigated the day-to-day associations between sleep and psychotic experiences bidirectionally on an item level. Sleep items included sleep onset latency, fragmentation, and quality. Psychosis items assessed a range of perceptual, cognitive, and bizarre thought content common in the CHR population. Results: Two of the seven psychosis variables were unidirectionally predicted by previous night's number of awakenings: every unit increase in number of nightly awakenings predicted a 0.27 and 0.28 unit increase in feeling unreal or paranoid the next day, respectively. No other sleep variables credibly predicted next-day psychotic symptoms or vice-versa. Conclusion: In this study, the relationship between sleep disturbance and APS appears specific to the item in question. However, some APS, including perceptual disturbances, had low levels of endorsement amongst this sample. Nonetheless, these results provide evidence for a unidirectional relationship between sleep and some APS in this population. [ABSTRACT FROM AUTHOR]
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- 2024
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3. Metacognitive reflection and insight therapy (MERIT) for patients with schizophrenia.
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de Jong, S., van Donkersgoed, R. J. M., Timmerman, M. E., aan het Rot, M., Wunderink, L., Arends, J., van Der Gaag, M., Aleman, A., Lysaker, P. H., and Pijnenborg, G. H. M.
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SCHIZOPHRENIA treatment ,COGNITIVE testing ,PSYCHOTHERAPY ,PSYCHOTHERAPY patients ,REFLECTION (Philosophy) ,STATISTICAL sampling ,PSYCHOSOCIAL factors ,RANDOMIZED controlled trials ,TREATMENT effectiveness ,PRE-tests & post-tests - Abstract
Background: Impaired metacognition is associated with difficulties in the daily functioning of people with psychosis. Metacognition can be divided into four domains: Self-Reflection, Understanding the Other's Mind, Decentration, and Mastery. This study investigated whether Metacognitive Reflection and Insight Therapy (MERIT) can be used to improve metacognition. Methods: This study is a randomized controlled trial. Patients in the active condition (n = 35) received forty MERIT sessions, the control group (n = 35) received treatment as usual. Multilevel intention-to-treat and completers analyses were performed for metacognition and secondary outcomes (psychotic symptomatology, cognitive insight, Theory of Mind, empathy, depression, self-stigma, quality of life, social functioning, and work readiness). Results: Eighteen out of 35 participants finished treatment, half the drop-out stemmed from therapist attrition (N = 5) or before the first session (N = 4). Intention-to-treat analysis demonstrated that in both groups metacognition improved between pre- and post-measurements, with no significant differences between the groups. Patients who received MERIT continued to improve, while the control group returned to baseline, leading to significant differences at follow-up. Completers analysis (18/35) showed improvements on the Metacognition Assessment Scale (MAS-A) scales Self Reflectivity and metacognitive Mastery at follow-up. No effects were found on secondary outcomes. Conclusions: On average, participants in the MERIT group were, based on MAS-A scores, at follow-up more likely to recognize their thoughts as changeable rather than as facts. MERIT might be useful for patients whose self-reflection is too limited to benefit from other therapies. Given how no changes were found in secondary measures, further research is needed. Limitations and suggestions for future research are discussed. [ABSTRACT FROM AUTHOR]
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- 2019
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4. Van beperkingen naar mogelijkheden door bekrachtiging.
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van der Gaag, M. and van der Plas, J.
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- 2016
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5. Angst: de interactie van verschillende leerniveaus.
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van der Gaag, M. and van der Plas, J.
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- 2016
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6. De analyse van de organisatie en het omvormen tot een positief uitnodigende omgeving.
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van der Gaag, M. and van der Plas, J.
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- 2016
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7. Het versterken van de zelfwaardering en eigenwaarde.
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van der Gaag, M. and van der Plas, J.
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- 2016
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8. Het cognitieve model en g-schema's bij ingrijpende gebeurtenissen.
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van der Gaag, M. and van der Plas, J.
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- 2016
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9. Gedragsveranderende programma's.
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van der Gaag, M. and van der Plas, J.
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- 2016
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10. Zelfcontrole en sociaal leren door imitatie.
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van der Gaag, M. and van der Plas, J.
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- 2016
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11. Gesprekstechnieken bij het stellen van doelen.
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van der Gaag, M. and van der Plas, J.
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- 2016
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12. De analyse van complexe gedragsinteracties.
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van der Gaag, M. and van der Plas, J.
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- 2016
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13. Gesprekstechnieken bij het motiveren tot verandering.
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van der Gaag, M. and van der Plas, J.
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- 2016
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14. De analyse van een vaardigheid en vaardigheidstraining.
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van der Gaag, M. and van der Plas, J.
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- 2016
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15. Gesprekstechnieken en assertief onderhandelen.
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van der Gaag, M. and van der Plas, J.
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- 2016
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16. Gesprekstechnieken.
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van der Gaag, M. and van der Plas, J.
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- 2016
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17. Omgaan met inadequaat gedrag.
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van der Gaag, M. and van der Plas, J.
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- 2016
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18. Het behouden van adequaat gedrag door bekrachtiging.
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van der Gaag, M. and van der Plas, J.
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- 2016
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19. Childhood trauma, psychosis liability and social stress reactivity: a virtual reality study.
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Veling, W., Counotte, J., Pot-Kolder, R., van Os, J., and van der Gaag, M.
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MENTAL illness risk factors ,WOUNDS & injuries ,MENTAL health ,SUBSTANCE-induced psychoses ,AFFECTIVE disorders ,PARANOIA ,POST-traumatic stress disorder ,PSYCHOLOGICAL stress ,MULTIPLE regression analysis ,PSYCHOLOGICAL factors ,CHILDREN ,DISEASE risk factors - Abstract
BackgroundChildhood trauma is associated with higher risk for mental disorders, including psychosis. Heightened sensitivity to social stress may be a mechanism. This virtual reality study tested the effect of childhood trauma on level of paranoid ideations and distress in response to social stress, in interaction with psychosis liability and level of social stress exposure.MethodSeventy-five individuals with higher psychosis liability (55 with recent onset psychotic disorder and 20 at ultra-high risk for psychosis) and 95 individuals with lower psychosis liability (42 siblings and 53 controls) were exposed to a virtual café in five experiments with 0–3 social stressors (crowded, other ethnicity and hostility). Paranoid ideation was measured after each experiment. Subjective distress was self-rated before and after experiments. Multilevel random regression analyses were used to test main effects of childhood trauma and interaction effects.ResultsChildhood trauma was more prevalent in individuals with higher psychosis liability, and was associated with higher level of (subclinical) psychotic and affective symptoms. Individuals with a history of childhood trauma responded with more subjective distress to virtual social stress exposures. The effects of childhood trauma on paranoia and subjective distress were significantly stronger when the number of virtual environmental stressors increased. Higher psychosis liability increased the effect of childhood trauma on peak subjective distress and stress reactivity during experiments.ConclusionsChildhood trauma is associated with heightened social stress sensitivity and may contribute to psychotic and affective dysregulation later in life, through a sensitized paranoid and stress response to social stressors. [ABSTRACT FROM PUBLISHER]
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- 2016
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20. Prolonged exposure and EMDR for PTSD v. a PTSD waiting-list condition: effects on symptoms of psychosis, depression and social functioning in patients with chronic psychotic disorders.
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de Bont, P. A. J. M., van den Berg, D. P. G., van der Vleugel, B. M., de Roos, C., de Jongh, A., van der Gaag, M., and van Minnen, A. M.
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TREATMENT of post-traumatic stress disorder ,SCHIZOAFFECTIVE disorders ,SCHIZOPHRENIA treatment ,EMDR (Eye-movement desensitization & reprocessing) ,HALLUCINATIONS ,LIFE skills ,LONGITUDINAL method ,PSYCHOLOGICAL tests ,STATISTICAL sampling ,COMORBIDITY ,RANDOMIZED controlled trials ,PRE-tests & post-tests ,BLIND experiment ,THERAPEUTICS - Abstract
BackgroundIn patients with psychotic disorders, the effects of psychological post-traumatic stress disorder (PTSD) treatment on symptoms of psychosis, depression and social functioning are largely unknownMethodIn a single-blind randomized controlled trial (RCT) 155 outpatients in treatment for psychosis (61.3% schizophrenic disorder, 29% schizoaffective disorder) were randomized to eight sessions prolonged exposure (PE; n = 53) or eye movement desensitization and reprocessing (EMDR) (n = 55), or a waiting-list condition (WL, n = 47) for treatment of their co-morbid PTSD. Measures were performed on (1) psychosis: severity of delusions (PSYRATS-DRS), paranoid thoughts (GPTS), auditory verbal hallucinations (PSYRATS-AHRS), and remission from psychotic disorder (SCI-SR-PANSS); (2) depression (BDI-II); (3) social functioning (PSP). Outcomes were compared at baseline, post-treatment, 6-month follow-up and over all data points.ResultsBoth PE and EMDR were significantly associated with less severe paranoid thoughts post-treatment and at 6-month follow-up, and with more patients remitting from schizophrenia, at post-treatment (PE and EMDR) and over time (PE). Moreover, PE was significantly associated with a greater reduction of depression at post-treatment and at 6-month follow-up. Auditory verbal hallucinations and social functioning remained unchanged.ConclusionsIn patients with chronic psychotic disorders PE and EMDR not only reduced PTSD symptoms, but also paranoid thoughts. Importantly, in PE and EMDR more patients accomplished the status of their psychotic disorder in remission. Clinically, these effects are highly relevant and provide empirical support to the notion that delivering PTSD treatment to patients with psychotic disorders and PTSD deserves increasing recognition and acceptance among clinicians. [ABSTRACT FROM PUBLISHER]
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- 2016
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21. Development of a stage-dependent prognostic model to predict psychosis in ultra-high-risk patients seeking treatment for co-morbid psychiatric disorders.
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Ising, H. K., Ruhrmann, S., Burger, N. A. F. M., Rietdijk, J., Dragt, S., Klaassen, R. M. C., van den Berg, D. P. G., Nieman, D. H., Boonstra, N., Linszen, D. H., Wunderink, L., Smit, F., Veling, W., and van der Gaag, M.
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PSYCHOSES ,PSYCHIATRIC treatment ,CHI-squared test ,COGNITIVE therapy ,CONFIDENCE intervals ,FISHER exact test ,HELP-seeking behavior ,LONGITUDINAL method ,NEUROPSYCHOLOGICAL tests ,PROBABILITY theory ,PSYCHOLOGICAL tests ,QUESTIONNAIRES ,REGRESSION analysis ,RESEARCH funding ,PSYCHOLOGICAL stress ,T-test (Statistics) ,MATHEMATICAL variables ,COMORBIDITY ,RANDOMIZED controlled trials ,PREDICTIVE tests ,PROPORTIONAL hazards models ,DATA analysis software ,DESCRIPTIVE statistics ,MANN Whitney U Test ,PROGNOSIS - Abstract
Background. Current ultra-high-risk (UHR) criteria appear insufficient to predict imminent onset of first-episode psychosis, as a meta-analysis showed that about 20% of patients have a psychotic outcome after 2 years. Therefore, we aimed to develop a stage-dependent predictive model in UHR individuals who were seeking help for co-morbid disorders. Method. Baseline data on symptomatology, and environmental and psychological factors of 185 UHR patients (aged 14-35 years) participating in the Dutch Early Detection and Intervention Evaluation study were analysed with Cox proportional hazard analyses. Results. At 18 months, the overall transition rate was 17.3%. The final predictor model included five variables: observed blunted affect [hazard ratio (HR) 3.39, 95% confidence interval (CI) 1.56-7.35, p < 0.001], subjective complaints of impaired motor function (HR 5.88, 95% CI 1.21-6.10, p = 0.02), beliefs about social marginalization (HR 2.76, 95% CI 1.14-6.72, p = 0.03), decline in social functioning (HR 1.10, 95% CI 1.01-1.17, p = 0.03), and distress associated with suspiciousness (HR 1.02, 95% CI 1.00-1.03, p = 0.01). The positive predictive value of the model was 80.0%. The resulting prognostic index stratified the general risk into three risk classes with significantly different survival curves. In the highest risk class, transition to psychosis emerged on average 58 months earlier than in the lowest risk class. Conclusions. Predicting a first-episode psychosis in help-seeking UHR patients was improved using a stage-dependent prognostic model including negative psychotic symptoms (observed flattened affect, subjective impaired motor functioning), impaired social functioning and distress associated with suspiciousness. Treatment intensity may be stratified and personalized using the risk stratification. [ABSTRACT FROM AUTHOR]
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- 2016
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22. Cannabis use and transition to psychosis in individuals at ultra-high risk: review and meta-analysis.
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Kraan, T., Koenders, L., de Haan, L., Velthorst, E., Zwaart, K., van der Gaag, M., Ising, H. K., and van den Berg, D.
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PSYCHOSES risk factors ,CANNABIS (Genus) ,CONFIDENCE intervals ,DOSE-effect relationship in pharmacology ,MEDICAL information storage & retrieval systems ,PSYCHOLOGY information storage & retrieval systems ,MEDLINE ,CLASSIFICATION of mental disorders ,META-analysis ,SUBSTANCE abuse ,SYSTEMATIC reviews ,ODDS ratio - Abstract
BackgroundPrevious research has established the relationship between cannabis use and psychotic disorders. Whether cannabis use is related to transition to psychosis in patients at ultra-high risk (UHR) for psychosis remains unclear. The present study aimed to review the existing evidence on the association between cannabis use and transition to psychosis in UHR samples.MethodA search of PsychInfo, Embase and Medline was conducted from 1996 to August 2015. The search yielded 5559 potentially relevant articles that were selected on title and abstract. Subsequently 36 articles were screened on full text for eligibility. Two random-effects meta-analyses were performed. First, we compared transition rates to psychosis of UHR individuals with lifetime cannabis use with non-cannabis-using UHR individuals. Second, we compared transition rates of UHR individuals with a current DSM-IV cannabis abuse or dependence diagnosis with lifetime users and non-using UHR individuals.ResultsWe found seven prospective studies reporting on lifetime cannabis use in UHR subjects (n = 1171). Of these studies, five also examined current cannabis abuse or dependence. Lifetime cannabis use was not significantly associated with transition to psychosis [odds ratio (OR) 1.14, 95% confidence interval (CI) 0.856–1.524, p = 0.37]. A second meta-analysis yielded an OR of 1.75 (95% CI 1.135–2.710, p = 0.01), indicating a significant association between current cannabis abuse or dependence and transition to psychosis.ConclusionsOur results show that cannabis use was only predictive of transition to psychosis in those who met criteria for cannabis abuse or dependence, tentatively suggesting a dose–response relationship between current cannabis use and transition to psychosis. [ABSTRACT FROM PUBLISHER]
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- 2016
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23. Metacognitive training for schizophrenia spectrum patients: a meta-analysis on outcome studies.
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van Oosterhout, B., Smit, F., Krabbendam, L., Castelein, S., Staring, A. B. P., and van der Gaag, M.
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SCHIZOPHRENIA treatment ,CHI-squared test ,COGNITIVE therapy ,CONFIDENCE intervals ,DELUSIONS ,INFORMATION storage & retrieval systems ,MEDICAL databases ,MEDICAL information storage & retrieval systems ,PSYCHOLOGY information storage & retrieval systems ,MEDLINE ,META-analysis ,SCHIZOPHRENIA ,SYSTEMATIC reviews ,SAMPLE size (Statistics) ,EFFECT sizes (Statistics) ,DESCRIPTIVE statistics - Abstract
Background.Metacognitive training (MCT) for schizophrenia spectrum is widely implemented. It is timely to systematically review the literature and to conduct a meta-analysis.Method.Eligible studies were selected from several sources (databases and expert suggestions). Criteria included comparative studies with a MCT condition measuring positive symptoms and/or delusions and/or data-gathering bias. Three meta-analyses were conducted on data gathering (three studies; 219 participants), delusions (seven studies; 500 participants) and positive symptoms (nine studies; 436 participants). Hedges’ g is reported as the effect size of interest. Statistical power was sufficient to detect small to moderate effects.Results.All analyses yielded small non-significant effect sizes (0.26 for positive symptoms; 0.22 for delusions; 0.31 for data-gathering bias). Corrections for publication bias further reduced the effect sizes to 0.21 for positive symptoms and to 0.03 for delusions. In blinded studies, the corrected effect sizes were 0.22 for positive symptoms and 0.03 for delusions. In studies using proper intention-to-treat statistics the effect sizes were 0.10 for positive symptoms and −0.02 for delusions. The moderate to high heterogeneity in most analyses suggests that processes other than MCT alone have an impact on the results.Conclusions.The studies so far do not support a positive effect for MCT on positive symptoms, delusions and data gathering. The methodology of most studies was poor and sensitivity analyses to control for methodological flaws reduced the effect sizes considerably. More rigorous research would be helpful in order to create enough statistical power to detect small effect sizes and to reduce heterogeneity. Limitations and strengths are discussed. [ABSTRACT FROM PUBLISHER]
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- 2016
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24. Cost-effectiveness of preventing first-episode psychosis in ultra-high-risk subjects: multi-centre randomized controlled trial.
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Ising, H. K., Smit, F., Veling, W., Rietdijk, J., Dragt, S., Klaassen, R. M. C., Savelsberg, N. S. P., Boonstra, N., Nieman, D. H., Linszen, D. H., Wunderink, L., and van der Gaag, M.
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PSYCHOSES ,COGNITIVE therapy ,MEDICAL care costs ,PSYCHOLOGICAL tests ,REGRESSION analysis ,RESEARCH funding ,COST analysis ,RANDOMIZED controlled trials ,QUALITY-adjusted life years ,DATA analysis software ,PREVENTION - Abstract
BackgroundAlthough there is evidence for the effectiveness of interventions for psychosis among ultra-high-risk (UHR) groups, health economic evaluations are lacking. This study aimed to determine the cost effectiveness and cost–utility of cognitive–behavioural therapy (CBT) to prevent first-episode psychosis.MethodThe Dutch Early Detection and Intervention Evaluation study was a randomized controlled trial of 196 UHR patients with an 18-month follow-up. All participants were treated with routine care (RC) for non-psychotic disorders. The experimental group (n = 95) received add-on CBT to prevent first-episode psychosis. We report the intervention, medical and travel costs, as well as costs arising from loss of productivity. Treatment response was defined as psychosis-free survival and quality-adjusted life years (QALYs) gained.ResultsIn the cost-effectiveness analysis, the proportion of averted psychoses was significantly higher in the CBT condition (89.5% v. 76.2%). CBT showed a 63.7% probability of being more cost effective, because it was less costly than RC by US$844 (£551) per prevented psychosis. In the cost–utility analysis, QALY health gains were slightly higher for CBT than for RC (0.60 v. 0.57) and the CBT intervention had a 52.3% probability of being the superior treatment because, for equal or better QALY gains, the costs of CBT were lower than those of RC.ConclusionsAdd-on preventive CBT for UHR resulted in a significant reduction in the incidence of first psychosis. QALY gains show little difference between the two conditions. The CBT intervention proved to be cost saving. [ABSTRACT FROM AUTHOR]
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- 2015
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25. Adapted cognitive–behavioural therapy required for targeting negative symptoms in schizophrenia: meta-analysis and meta-regression.
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Velthorst, E., Koeter, M., van der Gaag, M., Nieman, D. H., Fett, A.-K. J., Smit, F., Staring, A. B. P., Meijer, C., and de Haan, L.
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BackgroundThere is an increasing interest in cognitive–behavioural therapy (CBT) interventions targeting negative symptoms in schizophrenia. To date, CBT trials primarily focused on positive symptoms and investigated change in negative symptoms only as a secondary outcome. To enhance insight into factors contributing to improvement of negative symptoms, and to identify subgroups of patients that may benefit most from CBT directed at ameliorating negative symptoms, we reviewed all available evidence on these outcomes.MethodA systematic search of the literature was conducted in PsychInfo, PubMed and the Cochrane register to identify randomized controlled trials reporting on the impact of CBT interventions on negative symptoms in schizophrenia. Random-effects meta-analyses were performed on end-of-treatment, short-term and long-term changes in negative symptoms.ResultsA total of 35 publications covering 30 trials in 2312 patients, published between 1993 and 2013, were included. Our results showed studies’ pooled effect on symptom alleviation to be small [Hedges’ g = 0.093, 95% confidence interval (CI) −0.028 to 0.214, p = 0.130] and heterogeneous (Q = 73.067, degrees of freedom = 29, p < 0.001, τ2 = 0.081, I2 = 60.31) in studies with negative symptoms as a secondary outcome. Similar results were found for studies focused on negative symptom reduction (Hedges’ g = 0.157, 95% CI −0.10 to 0.409, p = 0.225). Meta-regression revealed that stronger treatment effects were associated with earlier year of publication, lower study quality and with CBT provided individually (as compared with group-based).ConclusionsThe co-occurring beneficial effect of conventional CBT on negative symptoms found in older studies was not supported by more recent studies. It is now necessary to further disentangle effective treatment ingredients of older studies in order to guide the development of future CBT interventions aimed at negative symptom reduction. [ABSTRACT FROM AUTHOR]
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- 2015
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26. Adapted cognitive–behavioural therapy required for targeting negative symptoms in schizophrenia: meta-analysis and meta-regression.
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Velthorst, E., Koeter, M., van der Gaag, M., Nieman, D. H., Fett, A.-K. J., Smit, F., Staring, A. B. P., Meijer, C., and de Haan, L.
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SCHIZOPHRENIA treatment ,PSYCHOSES ,COGNITIVE therapy ,CHI-squared test ,CONFIDENCE intervals ,INFORMATION storage & retrieval systems ,MEDICAL databases ,PSYCHOLOGY information storage & retrieval systems ,EVALUATION of medical care ,MEDLINE ,META-analysis ,ONLINE information services ,REGRESSION analysis ,RESEARCH funding ,SYSTEMATIC reviews ,EFFECT sizes (Statistics) ,RANDOMIZED controlled trials ,DATA analysis software ,PREVENTION - Abstract
BackgroundThere is an increasing interest in cognitive–behavioural therapy (CBT) interventions targeting negative symptoms in schizophrenia. To date, CBT trials primarily focused on positive symptoms and investigated change in negative symptoms only as a secondary outcome. To enhance insight into factors contributing to improvement of negative symptoms, and to identify subgroups of patients that may benefit most from CBT directed at ameliorating negative symptoms, we reviewed all available evidence on these outcomes.MethodA systematic search of the literature was conducted in PsychInfo, PubMed and the Cochrane register to identify randomized controlled trials reporting on the impact of CBT interventions on negative symptoms in schizophrenia. Random-effects meta-analyses were performed on end-of-treatment, short-term and long-term changes in negative symptoms.ResultsA total of 35 publications covering 30 trials in 2312 patients, published between 1993 and 2013, were included. Our results showed studies’ pooled effect on symptom alleviation to be small [Hedges’ g = 0.093, 95% confidence interval (CI) −0.028 to 0.214, p = 0.130] and heterogeneous (Q = 73.067, degrees of freedom = 29, p < 0.001, τ2 = 0.081, I2 = 60.31) in studies with negative symptoms as a secondary outcome. Similar results were found for studies focused on negative symptom reduction (Hedges’ g = 0.157, 95% CI −0.10 to 0.409, p = 0.225). Meta-regression revealed that stronger treatment effects were associated with earlier year of publication, lower study quality and with CBT provided individually (as compared with group-based).ConclusionsThe co-occurring beneficial effect of conventional CBT on negative symptoms found in older studies was not supported by more recent studies. It is now necessary to further disentangle effective treatment ingredients of older studies in order to guide the development of future CBT interventions aimed at negative symptom reduction. [ABSTRACT FROM PUBLISHER]
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- 2015
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27. Professioneel begeleiden door zelfbekrachtiging.
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van der Gaag, M. and van der Plas, J.
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- 2016
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28. 9 Cognitieve gedragstherapie bij persisterende symptomen.
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van der Gaag, M.
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- 2006
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29. Metacognitive group training for schizophrenia spectrum patients with delusions: a randomized controlled trial.
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van Oosterhout, B., Krabbendam, L., de Boer, K., Ferwerda, J., van der Helm, M., Stant, A. D., and van der Gaag, M.
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COGNITION ,DELUSIONS ,INTERVIEWING ,RESEARCH methodology ,MEDICAL cooperation ,QUESTIONNAIRES ,RESEARCH ,RESEARCH funding ,STATISTICAL sampling ,SCALE analysis (Psychology) ,SCHIZOPHRENIA ,SELF-evaluation ,SAMPLE size (Statistics) ,EFFECT sizes (Statistics) ,RANDOMIZED controlled trials ,BLIND experiment ,DATA analysis software ,DESCRIPTIVE statistics - Abstract
BackgroundMetacognitive training (MCT) for patients with psychosis is a psychological group intervention that aims to educate patients about common cognitive biases underlying delusion formation and maintenance, and to highlight their negative consequences in daily functioning.MethodIn this randomized controlled trial, 154 schizophrenia spectrum patients with delusions were randomly assigned to either MCT + treatment as usual (TAU) or TAU alone. Both groups were assessed at baseline, and again after 8 and 24 weeks. The trial was completed fully by 111 patients. Efficacy was measured with the Psychotic Symptom Rating Scales (PSYRATS) Delusions Rating Scale (DRS), and with specific secondary measures referring to persecutory ideas and ideas of social reference (the Green Paranoid Thoughts Scale, GPTS), cognitive insight (the Beck Cognitive Insight Scale, BCIS), subjective experiences of cognitive biases (the Davos Assessment of Cognitive Biases Scale, DACOBS) and metacognitive beliefs (the 30-item Metacognitions Questionnaire, MCQ-30). Economic analysis focused on the balance between societal costs and health outcomes (quality-adjusted life years, QALYs).ResultsBoth conditions showed a decrease of delusions. MCT was not more efficacious in terms of reducing delusions, nor did it change subjective paranoid thinking and ideas of social reference, cognitive insight or subjective experience of cognitive biases and metacognitive beliefs. The results of the economic analysis were not in favour of MCT + TAU.ConclusionsIn the present study, MCT did not affect delusion scores and self-reported cognitive insight, or subjective experience of cognitive biases and metacognitive beliefs. MCT was not cost-effective. [ABSTRACT FROM AUTHOR]
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- 2014
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30. Depressive symptoms are associated with (sub)clinical psychotic symptoms in patients with non-affective psychotic disorder, siblings and healthy controls.
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Klaassen, R. M. C., Heins, M., Luteijn, L. B., Van Der Gaag, M., and Van Beveren, N. J. M.
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SIBLINGS ,COMPARATIVE studies ,CONFIDENCE intervals ,MENTAL depression ,EPIDEMIOLOGY ,NEUROPSYCHOLOGICAL tests ,CLASSIFICATION of mental disorders ,PSYCHOSES ,RESEARCH funding ,SCHIZOPHRENIA ,LOGISTIC regression analysis ,DATA analysis ,SECONDARY analysis ,SEVERITY of illness index ,DATA analysis software ,DESCRIPTIVE statistics - Abstract
Background. Depression is a clinically relevant dimension, associated with both positive and negative symptoms, in patients with schizophrenia. However, in siblings it is unknown whether depression is associated with subclinical positive and negative symptoms. Method. Depressive symptoms and their association with positive and negative symptoms were examined in 813 healthy siblings of patients with a non-affective psychotic disorder, 822 patients and 527 healthy controls. Depressive episodes meeting DSM-IV-TR criteria (lifetime) and depressed mood (lifetime) were assessed with the Comprehensive Assessment of Symptoms and History (CASH) in all three groups. In the patient group, the severity of positive and negative psychosis symptoms was assessed with the CASH. In the siblings and healthy controls, the severity of subclinical psychosis symptoms was assessed with the Community Assessment of Psychic Experiences (CAPE). Results. Patients reported more lifetime depressed mood and more depressive episodes than both siblings and controls. Siblings had a higher chance of meeting lifetime depressive episodes than the controls; no significant differences in depressed mood were found between siblings and controls. In all three groups the number and duration of depressive symptoms were associated with (sub)clinical negative symptoms. In the patients and siblings the number of depressive symptoms was furthermore associated with (sub)clinical positive symptoms. Finally, lifetime depressed mood showed familial clustering but this clustering was absent for lifetime depressive episodes. Conclusions. These findings suggest that a co-occurring genetic vulnerability for both depressive and psychotic symptomatology exists on a clinical and a subclinical level. [ABSTRACT FROM AUTHOR]
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- 2013
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31. Detection of people at risk of developing a first psychosis: comparison of two recruitment strategies.
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Rietdijk, J., Klaassen, R., Ising, H., Dragt, S., Nieman, D. H., van de Kamp, J., Cuijpers, P., Linszen, D., and van der Gaag, M.
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PSYCHOSES ,HELP-seeking behavior ,MENTAL health services ,MULTIVARIATE analysis ,SOCIAL anxiety ,PSYCHOLOGICAL distress ,PATIENTS - Abstract
Rietdijk J, Klaassen R, Ising H, Dragt S, Nieman DH, van de Kamp J, Cuijpers P, Linszen D, van der Gaag M. Detection of people at risk of developing a first psychosis: comparison of two recruitment strategies. Objective: Better recruitment strategies are needed to improve the identification of people at ultra-high risk of developing psychosis. This study explores the effectiveness of two recruitment strategies: a screening method in a consecutive help-seeking population entering secondary mental health services for non-psychotic problems vs. a population referred to the diagnostic center of an early-psychosis clinic. Method: From February 2008 to February 2010, all general practitioner and self-referrals (aged 18-35 years) to the secondary mental healthcare service in The Hague and Zoetermeer were screened with the Prodromal Questionnaire; patients who scored above the cutoff of 18 and had a decline in social functioning were assessed using the Comprehensive Assessment of At-Risk Mental States (CAARMS). All referrals (aged 14-35 years) to the diagnostic center in Amsterdam were also assessed with the CAARMS. Results: The screening detected a three-fold higher prevalence of at-risk mental states: these subjects were older and more often female. manova showed significantly higher scores for the screened population on depression, social anxiety, distress with positive symptoms, and a higher rate of transition to psychosis within 12 months. Conclusion: The screening method detects more patients with at-risk mental states than the referral method. The latter method is biased to young male patients in an earlier prodromal stage and a lower transition rate. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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32. Ethnicity and baseline symptomatology in patients with an At Risk Mental State for psychosis.
- Author
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Velthorst, E., Nieman, D. H., Veling, W., Klaassen, R. M., Dragt, S., Rietdijk, J., Ising, H., Wunderink, L., Linszen, D. H., de Haan, L., and van der Gaag, M.
- Subjects
CHI-squared test ,INTERVIEWING ,NEUROPSYCHOLOGICAL tests ,RESEARCH methodology ,MINORITIES ,PSYCHOLOGICAL tests ,PSYCHOSES ,RACE ,SCALES (Weighing instruments) ,STATISTICS ,T-test (Statistics) ,DISEASE prevalence ,CROSS-sectional method ,SEVERITY of illness index ,DATA analysis software - Abstract
BackgroundEthnicity has been associated with different incidence rates and different symptom profiles in young patients with psychotic-like disorders. No studies so far have examined the effect of ethnicity on symptoms in people with an At Risk Mental State (ARMS).MethodIn this cross-sectional study, we analysed the relationship between ethnicity and baseline data on the severity of psychopathology scores in 201 help-seeking patients who met the ARMS criteria and agreed to participate in the Dutch Early Detection and Intervention (EDIE-NL) trial. Eighty-seven of these patients had a non-Dutch ethnicity. We explored the possible mediating role of ethnic identity.ResultsHigher rates of negative symptoms, and of anhedonia in particular, were found in the ethnic minority group. This result could be attributed mainly to the Moroccan-Dutch and Turkish-Dutch subgroups, who also presented with more depression symptoms when the groups were examined separately. The ethnic minority group displayed a lower level of ethnic group identity compared to the immigrants of the International Comparative Study of Ethnocultural Youth (ICSEY). Ethnic identity was inversely related to symptoms in the Moroccan-Dutch patient group.ConclusionsThe prevalence of more severe negative symptoms and depression symptoms in ethnic minority groups deserves more attention, as the experience of attenuated positive symptoms when accompanied by negative symptoms or distress has proven to be predictive for transition to a first psychotic episode. [ABSTRACT FROM PUBLISHER]
- Published
- 2012
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33. Recovery style predicts remission at one-year follow-up in outpatients with schizophrenia spectrum disorders.
- Author
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Staring AB, van der Gaag M, and Mulder CL
- Published
- 2011
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34. Economic Aspects of Peer Support Groups for Psychosis.
- Author
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Stant, A. D., Castelein, S., Bruggeman, R., van Busschbach, J. T., van der Gaag, M., Knegtering, H., and Wiersma, D.
- Subjects
ANALYSIS of variance ,CONFIDENCE intervals ,COST effectiveness ,MEDICAL care costs ,PROBABILITY theory ,PSYCHOSES ,AFFINITY groups ,SOCIAL support - Abstract
Peer support groups are rarely available for patients with psychosis, despite potential clinical and economic advantages of such groups. In this study, 106 patients with psychosis were randomly allocated to minimally guided peer support in addition to care as usual (CAU), or CAU only. No relevant differences between mean total costs of both groups were found, nor were there significant differences in WHOQoL-Bref outcomes. Intervention adherence had a substantial impact on the results. It was concluded that minimally guided peer support groups for psychosis do not seem to affect overall healthcare expenses. Positive results of additional outcomes, including a significant increase in social contacts and esteem support, favour the wider implementation of such groups. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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35. Treatment adherence therapy in people with psychotic disorders: randomised controlled trial.
- Author
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Staring, A. B. P., Van der Gaag, M., Koopmans, G. T., Selten, J. P., Van Beveren, J. M., Hengeveld, M. W., Loonen, A. J. M., and Mulder, C. L.
- Subjects
PATIENT compliance ,RANDOMIZED controlled trials ,PSYCHOSES ,ANTIPSYCHOTIC agents ,THERAPEUTICS - Abstract
Background: Interventions to improve adherence to treatment in people with psychotic disorders have produced inconclusive results. We developed a new treatment, treatment adherence therapy (TAT), whose intervention modules are tailored to the reasons for an individual's non-adherence.Aims: To examine the effectiveness of TAT with regard to service engagement and medication adherence in out-patients with psychotic disorders who engage poorly.Method: Randomised controlled study of TAT v. treatment as usual (TAU) in 109 out-patients. Most outcome measurements were performed by masked assessors. We used intention-to-treat multivariate analyses (Dutch Trial Registry: NTR1159).Results: Treatment adherence therapy v. TAU significantly benefited service engagement (Cohen's d = 0.48) and medication adherence (Cohen's d = 0.43). Results remained significant at 6-month follow-up for medication adherence. Near-significant effects were also found regarding involuntary readmissions (1.9% v. 11.8%, P = 0.053). Symptoms and quality of life did not improve.Conclusions: Treatment adherence therapy helps improve engagement and adherence, and may prevent involuntary admission. [ABSTRACT FROM AUTHOR]- Published
- 2010
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36. Early intervention in patients at ultra high risk of psychosis: benefits and risks.
- Author
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De Koning, M. B., Bloemen, O. J. N., Van Amelsvoort, T. A. M. J., Becker, H. E., Nieman, D. H., Van Der Gaag, M., and Linszen, D. H.
- Subjects
PSYCHOSES ,OPERANT behavior ,ANTIPSYCHOTIC agents ,BEHAVIOR therapy ,ANTIDEPRESSANTS ,CLINICAL trials ,PREVENTION - Abstract
Objective: Prediction of transition to psychosis in the prodromal phase of schizophrenia has raised interest in intervention prior to the onset of frank psychosis. The aim of this review was to examine whether interventions in the prodromal phase have a favourable benefit/risk ratio. Method: A literature search in PubMed, EMBASE and PsycINFO was performed. Results: Three randomized clinical trials with antipsychotic medication and/or cognitive behavioural therapy as clinical intervention suggested a positive effect at the end of treatment, but no significant differences were found at the end of follow-up periods from 1 to 4 years. Naturalistic studies present a hypothesis about a possible preventive effect of antidepressive medication. The results of eight other studies are more difficult to interpret. Side-effects of antipsychotic medication and non-adherence with medication are essential problems. Conclusion: At the present time, the data concerning the benefits and risks do not justify prodromal intervention as standard clinical practice. [ABSTRACT FROM AUTHOR]
- Published
- 2009
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37. Measuring empowerment among people with psychotic disorders: a comparison of three instruments.
- Author
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Castelein S, van der Gaag M, Bruggeman R, van Busschbach JT, Wiersma D, Castelein, Stynke, van der Gaag, Mark, Bruggeman, Richard, van Busschbach, Jooske T, and Wiersma, Durk
- Abstract
Objective: This study compared three instruments that are used to measure empowerment of people with psychotic disorders. The study evaluated internal consistency, discriminant and convergent validity, sensitivity to symptom levels, and clinical usefulness.Methods: Fifty patients in the Netherlands were administered the Empowerment Scale (ES), the Personal Empowerment Scale (PES), and the Mental Health Confidence Scale (MHCS).Results: The MHCS had good internal consistency, whereas the levels for the ES and PES were just below what would be considered acceptable. The instruments demonstrated moderate correlations between total scores; correlations between subscale scores were weaker. Scores for all three instruments were comparably associated with symptom severity.Conclusions: All three instruments measure some aspect of empowerment among persons with severe mental illness. However, empowerment is too broadly defined to allow these instruments to have convergent validity. Among patients with psychotic disorders, the MHCS is recommended because it has good psychometric qualities and is clinically useful. [ABSTRACT FROM AUTHOR]- Published
- 2008
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- View/download PDF
38. The effectiveness of peer support groups in psychosis: a randomized controlled trial.
- Author
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Castelein, S., Bruggeman, R., Van Busschbach, J. T., Van Der Gaag, M., Stant, A. D., Knegtering, H., and Wiersma, D.
- Subjects
PSYCHIATRY ,SCHIZOPHRENIA ,PSYCHIATRIC nursing ,QUALITY of life ,SOCIAL groups ,SOCIAL networks - Abstract
Objective: To investigate the effect of a (minimally) guided peer support group (GPSG) for people with psychosis on social network, social support, self-efficacy, self-esteem, and quality of life, and to evaluate the intervention and its economic consequences. Method: In a multi-center randomized controlled trial with 56 patients in the peer support group and 50 patients in the control condition, patients were assessed at baseline and after the last meeting at 8 months. Results: The experimental group showed GPSG to have a positive effect on social network and social support compared with the control condition. In the experimental condition, high attenders favored over low attenders on increased social support, self-efficacy, and quality of life. Economic evaluation demonstrated groups to be without financial consequences. The GPSG-intervention was positively evaluated. Conclusion: Peer support groups are a useful intervention for people suffering from psychosis by improving their social network. [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF
39. Development of a guideline for the water bolus temperature in superficial hyperthermia.
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Van Der Gaag, M. L., De Bruijne, M., Samaras, T., Van Der Zee, J., and Van Rhoon, G. C.
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FEVER ,BODY temperature ,TISSUES ,ANATOMY ,MEDICINE - Abstract
Purpose: The research presented in this work investigates the influence of the water bolus temperature on temperature distributions in tissue during superficial hyperthermia treatments using Lucite cone applicators. The goal of the research was to develop a guideline for the selection of the water bolus temperature based on 3-D electromagnetic and thermal modelling. Methods: A 3-D model was set up to simulate an abstraction of the treatment. In the model a convection coefficient for the water bolus to skin surface was employed. In order to simulate the heat balance as realistically as possible, convection coefficients were measured for different water boluses and ranged from 70-152 W (m2 K)-1. The model was evaluated by simulating three clinical treatments and comparing the outcome of the model to the clinical measurements. Results: The model was found to predict the temperature distribution well on a global view; root mean square errors between 0.66-1.5°C were found for the three treatments. For some temperature probes a deviation of 1.5-2.0°C between measured and predicted temperature was found. These large deviations can be explained by local variations in cooling by blood vessels, tissue inhomogeneity, a varying convection coefficient of the water bolus and of course the complexity of the anatomy. Conclusions: The model was used to set up guidelines for the water bolus temperature selection in clinical practice for the target depths and applicator arrays used in the Rotterdam Erasmus Medical Center. [ABSTRACT FROM AUTHOR]
- Published
- 2006
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- View/download PDF
40. An Intervention Study to Prevent Relapse in Patients With Schizophrenia.
- Author
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Van Meijel, B., Kruitwagen, C., Van der Gaag, M., Kahn, R. S., and Grypdonck, M. H. F.
- Subjects
DISEASE relapse ,SCHIZOPHRENIA ,PEOPLE with schizophrenia ,PSYCHOSES ,PSYCHIATRIC nursing - Abstract
Purpose: To determine whether the use of relapse prevention plans (RPPs) in nursing practice is an effective intervention in reducing relapse rates among patients with schizophrenia. Design and Methods: Experimental design. Patients with schizophrenia (or a related psychotic disorder) and nurses from three mental health organizations were randomly assigned to either an experimental (RPP) or control condition (care as usual). The primary outcome measure was the psychotic relapses in the research groups. Results: The relapse rates in the experimental and control groups after 1-year follow-up were 12.5% and 26.2%, respectively ( p=.12, ns). The relative risk of a relapse in the experimental versus the control group was 0.48 (ns). Conclusions: In this study no statistically significant effects of the intervention were found. Effectiveness research in this area should be continued with larger sample sizes and longer follow-up periods. [ABSTRACT FROM AUTHOR]
- Published
- 2006
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41. Factors influencing the upper temperature tolerances of three mussel species in a brackish water canal: Size, season and laboratory protocols.
- Author
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Rajagopal, S., Van der Velde, G., Van der Gaag, M., and Jenner, H. A.
- Subjects
MUSSELS ,TEMPERATURE ,POWER plants ,ZEBRA mussel ,MORTALITY - Abstract
Mussels are the most problematic organisms encountered in the water intake systems of electrical power plants. Various fouling control measures are adopted, among which heat treatment is considered the relatively more attractive from economic and ecological points of view. Thermal tolerance experiments were carried out to determine the effects of mussel size (2 – 20  mm shell length), season (breeding vs non-breeding), nutritional status (fed vs non-fed), acclimation temperature (5 – 25°C) and acclimation salinity (1 – 35‰) on the mortality pattern of three important mussel species, viz. a freshwater mussel Dreissena polymorpha , a brackish water mussel Mytilopsis leucophaeata and a marine mussel Mytilus edulis under different temperatures (36 – 41°C). The mussels in the 10  mm size group exposed to 36°C showed 100% mortality after 38  min ( D. polymorpha ), 84  min ( M. edulis ) and 213  min ( M. leucophaeata ). The effect of mussel size on M. edulis and M. leucophaeata mortality at different temperatures was significant, with the largest size group of mussels showing greater resistance, while no significant size-dependence was observed in the case of D. polymorpha . All the three mussel species collected during the non-breeding season (November – April) were more tolerant (by about 40 – 45%) to temperature than those collected during breeding season (June – October). Nutritional status had no significant influence on the thermal tolerance of the three mussels; fed and non-fed mussels showed 100% mortality at comparable rates. Acclimation temperature had a significant effect on the mortality of all three species. Survival time at any given target temperature increased with increasing acclimation temperature. The acclimation salinity showed no significant effect on the thermal tolerance of the three mussel species. In comparison, M. leucophaeata was more tolerant to high temperature stress than the other two species. The present studies clearly show that various factors can influence the mortality of D. polymorpha , M. edulis and M. leucophaeata to elevated temperatures. The results, therefore, suggest that if heat treatment were to be used as a control measure for these mussels, it has to be employed judiciously, depending on the mussel species, mussel size, breeding season, water temperature and salinity. [ABSTRACT FROM AUTHOR]
- Published
- 2005
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- View/download PDF
42. Control of Brackish Water Fouling Mussel, Mytilopsis leucophaeata (Conrad), with Sodium Hypochlorite.
- Author
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Rajagopal, S., van der Gaag, M., van der Velde, G., and Jenner, H. A.
- Subjects
FOULING organisms ,AQUATIC animals ,MUSSELS ,SALINE waters ,SODIUM salts ,ZEBRA mussel - Abstract
Though the Conrad's false mussel, Mytilopsis leucophaeata, is an important fouling animal in industrial cooling water systems, there are no published reports on the tolerance of this species to chlorination. A series of experiments was conducted to determine the effects of mussel size (2–20 mm shell length), season (breeding versus nonbreeding), nutritional status (fed versus starved) and acclimation temperature (5–30°C) on the mortality pattern of M. leucophaeata under continuous chlorination (0.25–5 mg/L). The effect of mussel size on M. leucophaeata mortality in the presence of chlorine was significant, with 10 mm size group mussels showing greater resistance. At 0.25 mg/L residual chlorine, 2 mm size group mussels took 89 days to reach 100% mortality, whereas 10 mm size group mussels took 109 days. M. leucophaeata collected during nonbreeding season (December–April) was more tolerant to chlorine than those collected during breeding season (June–October). Nutritional status of the mussel had no significant influence on the chlorine tolerance of the mussel: fed and starved mussels succumbed to chlorine at equal rates. The effect of acclimation temperature on M. leucophaeata mortality in the presence of chlorine was significant. At 0.5 mg/L residual chlorine, mussels acclimated at 5°C required 99 days to reach 95% mortality, whereas mussels acclimated at 30°C required 47 days. A comparison of present data with previous reports suggests that resistance of M. leucophaeata to chlorination is higher than other mussel species causing fouling problems in The Netherlands (Mytilus edulis and Dreissena polymorpha). Correspondence to: S. Rajagopal; email: raju@sci.kun.nl --> [ABSTRACT FROM AUTHOR]
- Published
- 2002
- Full Text
- View/download PDF
43. Sublethal Responses of Zebra Mussel, Dreissena polymorpha to Low-level Chlorination: an Experimental Study.
- Author
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Rajagopal, S., Van Der Velde, G., Van Der Gaag, M., and Jenner, H. A.
- Subjects
ZEBRA mussel ,CHLORINATION ,FOULING ,CHLORINE ,PHYSIOLOGY - Abstract
Chlorination is a widely used method to combat zebra mussel fouling in industrial cooling water systems. However, there is paucity of information on the sublethal effects of low-level chlorination on the zebra mussels. The physiological behaviour (shell valve movement, filtration rate, foot activity index and byssus thread production) and the byssus thread strength of different size groups (between 5 and 20 mm shell length) of zebra mussel, Dreissena polymorpha (Pallas), were studied at different chlorine concentrations (0.1-1.0 mg l -1 ) in the laboratory. The results indicated that D. polymorpha was able to sense chlorine at levels as low as 0.1 mg l -1 and this significantly reduced their physiological activities (9%-18%). D. polymorpha also showed a progressive reduction in physiological activities when chlorine concentrations were increased from 0 to 0.5 mg l -1 . However, no significant differences in physiological activities were observed between 0.5 and 1.0 mg l -1 chlorine residuals ( e.g. 89% and 93% reduction in foot activity index at 0.5 and 1.0 mg l -1 , respectively). Shell opening frequencies of D. polymorpha in control experiments (0 mg l -1 residual chlorine) were about 18 times higher than those at 0.5 mg l -1 residual chlorine. Continuous dosing of at least 0.5 mg l -1 residual chlorine was found to be required before shell opening was critically impaired. Therefore, 0.5 mg l -1 residual chlorine appears to be the minimum chlorine level to be dosed continuously, for the successful control of D. polymorpha . The resistance of D. polymorpha to chlorine appeared to be lower than that for other mussel species in The Netherlands viz. Mytilus edulis L. and Mytilopsis leucophaeata (Conrad). [ABSTRACT FROM AUTHOR]
- Published
- 2002
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- View/download PDF
44. The practice of early recognition and early intervention to prevent psychotic relapse in patients with schizophrenia: an exploratory study. Part 1.
- Author
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van Meijel B, Van Der Gaag M, Kahn RS, and Grypdonck M
- Subjects
DISEASE relapse prevention ,PEOPLE with schizophrenia - Abstract
In this article we describe the findings of an exploratory study into the application of early recognition and early intervention methods aimed at prevention of psychotic relapses in patients with schizophrenia. We addressed several models of symptom recognition plans and indicated how patients, healthcare professionals and other persons involved may be able to list and evaluate early warning signs systematically. We also paid attention to the role of the patient's family and to the potential effects of using early recognition and early intervention methods. In a follow-up article (part 2), we will focus more specifically on factors which favourably or adversely affect the use of early recognition and early intervention methods. The results of this exploratory study will be used to design an intervention protocol for nursing staff to serve as a tool for preparing symptoms recognition plans with the individual patient and his/her social network. [ABSTRACT FROM AUTHOR]
- Published
- 2002
- Full Text
- View/download PDF
45. The practice of early recognition and early intervention to prevent psychotic relapse in patients with schizophrenia: an exploratory study. Part 2.
- Author
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van Meijel B, Van Der Gaag M, Kahn RS, and Grypdonck M
- Subjects
DISEASE relapse prevention ,PEOPLE with schizophrenia - Abstract
In this article we describe the findings of an exploratory study into the application of early recognition and early intervention methods aimed at prevention of psychotic relapses in patients with schizophrenia. Following the results we described in part 1, we now focus specifically on factors which favourably or adversely affect the use of early recognition and early intervention methods. The following issues will be addressed: (i) information and education; (ii) attitude of health care professionals; (iii) the patient's insight; (iv) acceptance of illness; (v) motivation; (vi) other relevant patient characteristics; and (vii) continuity of care. Finally, the implications of the findings for the development of a nursing intervention protocol will be discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2002
- Full Text
- View/download PDF
46. Field Research for the Authorisation of Pesticides.
- Author
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Van Dijk, H., Brussaard, L., Stein, A., Baerselman, F., De Heer, H., Brock, T., Van Donk, E., Vet, L., Van der Gaag, M., Van Gestel, C., Van der Hoeven, N., De Jong, F., Van der Linden, A., Van Noort, P., Oomen, P., and Van Vliet, P.
- Abstract
On request of the Dutch government a committee of the Health Council of the Netherlands has reviewed the role that results of field research in its broadest sense ( i.e., including multi-species toxicity tests in the laboratory, research on model ecosystems et cetera) can play in ecotoxicological risk assessment for the authorisation of pesticides. The Committee believes that field research can provide valuable additional data about the exposure of non-target organisms and the resultant effects at population, community and ecosystem level. However, it frequently is unclear how these data might be used in reaching a decision about authorisation. To solve this problem, it is necessary to specify what is understood by “unacceptable damage”. Both more clearly formulated protection goals of the government and a better understanding of the ecological significance of effects are needed to clarify this. Furthermore, the Committee points out that the statistical power of field trials must be sufficient to allow for the detection of changes that might be regarded as ecologically relevant. Finally, it recommends keeping a finger on the pulse in relation to authorised pesticides by monitoring their presence in environmental compartments and by investigating their role in suddenly occurring mortality among conspicuous animal species, such as birds, fish and honeybees. This kind of research forms a safety net for substances that have been wrongly authorised. [ABSTRACT FROM AUTHOR]
- Published
- 2000
- Full Text
- View/download PDF
47. The dynamics of pAL2-1 homologous linear plasmids in Podospora anserina.
- Author
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van der Gaag, M., Debets, A. J. M., Osiewacz, H. D., and Hoekstra, R. F.
- Abstract
A natural population of recently isolated Podospora anserina strains was screened for homologues of the linear longevity-inducing plasmid pAL2-1. Of the 78 wild-type isolates, 14 hybridised with a pAL2-1 specific probe, half of which contained a single plasmid and the other half multiple plasmid copies (plasmid family). All strains except one plasmid-containing strain, senesced normally. However, no inserted plasmid sequences were detected in the mitochondrial DNA, as was the case for the longevity-inducing pAL2-1 plasmid. Occasional loss of plasmids and of repeated plasmid sequences occurred during sexual transfer. Plasmid transmission was equally efficient for mono- and dikaryotic spores and was independent of the genetic background of the strains. Furthermore, horizontal transfer experiments showed that the linear plasmid could easily infect plasmid-free strains. Horizontal transfer was even observed between strains showing a clear vegetative incompatibility response (barrage). The linear plasmids are inherited maternally; however, paternal transmission was observed in crosses between confronted vegetative-incompatible strains. Paternal transmission of the plasmid was never observed using isolated spermatia for fertilisation, showing that mitochondrial plasmids can only gain access to maternal sexual reproductive structures following horizontal transfer. These findings have implications for both the function of vegetative incompatibility in fungi and for the mechanism of maintenance of linear plasmids. [ABSTRACT FROM AUTHOR]
- Published
- 1998
- Full Text
- View/download PDF
48. Stages of dietary change among nationally-representative samples of adults in the European Union.
- Author
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de Graaf, C., Van der Gaag, M., Kafatos, A., Lennernas, M., and Kearney, J.M.
- Subjects
DIET -- Social aspects - Abstract
Objective: To investigate the distribution across the different stages of change for each of the 15 participating European countries, and the effect of socio-demographic variables such as sex and education on this distribution. Also to assess the relationships between stages of change and influences of food choice, and other variables. Design: A cross-sectional study in which quota-controlled, nationally-representative samples of approximately 1000 adults from each country completed a face-to-face interview-assisted questionnaire. Setting: The survey was conducted between October 1995 and February 1996 in the 15 member states of the European Union. Subjects: 14 331 subjects (aged 15 y upwards) completed the questionnaire. Data were weighted by population size for each country and by sex, age and regional distribution within each member state. Subjects were divided into five different categories according to their attitudes towards 'changing their eating habits in order to eat healthier': (1) Precontemplation; do not consider any changes, (2) Contemplation; consider changes, (3) Decision; make plans to change, (4) Action; carry out the changes, and (5) Maintenance; maintained changes for more than six months. Results: 52% of the subjects were in the precontemplation stage, whereas 31% of the subjects were in the maintenance stage. Two, one, and seven percent of subjects were in the contemplation, decision and action stage, respectively. In the Mediterranean countries, and in Germany, there were more people (55-64%) in the precontemplation stage, whereas in the Scandinavian countries there were less people in precontemplation stage (20-38%). The opposite was tree for the maintenance stage, whereas women and people with a higher education level tended to be more in the maintenance stage. With respect to influences on food choice, subjects in precontemplation stage found that taste was more important, whereas people in maintenance stage found that health was more important. Conclusions: The stages of change model makes a useful distinction between people with different attitudes towards nutrition and health. Nutrition education can benefit from this distinction. [ABSTRACT FROM AUTHOR]
- Published
- 1997
49. Letter to the Editor: In reply to the correspondence of Johannes Rentzsch, Kristin Koller and Golo Kronenberg.
- Author
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Kraan, T. C., Velthorst, E., de Haan, L., and van der Gaag, M.
- Subjects
MENTAL illness risk factors ,ALCOHOLISM ,CANNABIS (Genus) ,CLASSIFICATION of mental disorders ,SUBSTANCE abuse - Abstract
The article presents the authors' response to J. Rentzsch et al.'s commentary regarding their article "Cannabis Use and Transition to Psychosis in Individuals at Ultra-high Risk: Review and Meta-Analysis" which raised questions about the methodology and interpretation of findings. They agree that the relationship between cannabis use and psychosis needs further research and believe their meta-analysis contributed an important part in unravelling said relationship.
- Published
- 2016
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- View/download PDF
50. Effectiveness of trauma-focused treatment for patients with psychosis with and without the dissociative subtype of post-traumatic stress disorder.
- Author
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van Minnen, A., van der Vleugel, B. M., van den Berg, D. P. G., de Bont, P. A. J. M., de Roos, C., van der Gaag, M., and de Jongh, A.
- Subjects
TRAUMA centers ,PSYCHOSES ,POST-traumatic stress disorder ,HEALTH outcome assessment ,EMOTIONS ,PATIENTS ,TREATMENT of post-traumatic stress disorder ,PSYCHIATRIC treatment ,BEHAVIOR therapy ,COMPARATIVE studies ,DISSOCIATIVE disorders ,EMDR (Eye-movement desensitization & reprocessing) ,RESEARCH methodology ,MEDICAL cooperation ,RESEARCH ,EVALUATION research ,THERAPEUTICS - Abstract
This study presents secondary analyses of a recently published trial in which post-traumatic stress disorder (PTSD) patients with psychosis (n = 108) underwent 8 sessions of trauma-focused treatment, either prolonged exposure (PE) or eye movement desensitisation and reprocessing (EMDR) therapy. 24.1% fulfilled the criteria for the dissociative subtype, a newly introduced PTSD subtype in DSM-5. Treatment outcome was compared for patients with and without the dissociative subtype of PTSD. Patients with the dissociative subtype of PTSD showed large reductions in clinician-administered PTSD scale (CAPS) score, comparable with patients without the dissociative subtype of PTSD. It is concluded that even in a population with severe mental illness, patients with the dissociative subtype of PTSD do benefit from trauma-focused treatments without a pre-phase of emotion regulation skill training and should not be excluded from these treatments. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
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