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"Few studies"
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Performance of several types of beta-binomial models in comparison to standard approaches for meta-analyses with very few studies
Background
Meta-analyses are used to summarise the results of several studies on a specific research question. Standard methods for meta-analyses, namely inverse variance random effects models, have unfavourable properties if only very few (2 – 4) studies are available. Therefore, alternative meta-analytic methods are needed. In the case of binary data, the “common-rho” beta-binomial model has shown good results in situations with sparse data or few studies. The major concern of this model is that it ignores the fact that each treatment arm is paired with a respective control arm from the same study. Thus, the randomisation to a study arm of a specific study is disrespected, which may lead to compromised estimates of the treatment effect.
The aim of this simulation study was to compare the “common-rho” beta-binomial model and several other beta-binomial models with standard meta-analyses models, including generalised linear mixed models and several inverse variance random effects models.
Methods
We conducted a simulation study comparing beta-binomial models and various standard meta-analysis methods. The design of the simulation aimed to consider meta-analytic situations occurring in practice.
Results
No method performed well in scenarios with only 2 studies in the random effects scenario. In this situation, a fixed effect model or a qualitative summary of the study results may be preferable. In scenarios with 3 or 4 studies, most methods satisfied the nominal coverage probability. The “common-rho” beta-binomial model showed the highest power under the alternative hypothesis.
Conclusion
The “common-rho” beta-binomial appears to be a good option for meta-analyses of very few studies. As residual concerns about the consequences of disrespecting randomisation may still exist, we recommend a sensitivity analysis with a standard meta-analysis method that respects randomisation.
Journal Article
The impact of brief intensive trauma-focused treatment for PTSD on symptoms of borderline personality disorder
Background: It is generally recommended to exercise caution in applying trauma-focused treatment to individuals with posttraumatic stress disorder (PTSD) and comorbid borderline personality disorder (BPD).
Objective: To investigate the effects of a brief, intensive, direct trauma-focused treatment programme for individuals with PTSD on BPD symptom severity.
Methods: Individuals (n = 72) with severe PTSD (87.5% had one or more comorbidities; 52.8% fulfilled the criteria for the dissociative subtype of PTSD) due to multiple traumas (e.g. 90.3% sexual abuse) participated in an intensive eight-day trauma-focused treatment programme consisting of eye movement desensitization and reprocessing (EMDR) and prolonged exposure (PE) therapy, physical activity, and psychoeducation. Treatment did not include any form of stabilization (e.g. emotion regulation training) prior to trauma-focused therapy. Assessments took place at pre- and post-treatment (Borderline Symptom List, BSL-23; PTSD symptom severity, Clinician Administered PTSD Scale for DSM-5, CAPS-5), and across the eight treatment days (PTSD Checklist, PCL-5).
Results: Treatment resulted in significant decreases of BPD symptoms (Cohen's d = 0.70). Of the 35 patients with a positive screen for BPD at pre-treatment, 32.7% lost their positive screen at post-treatment. No adverse events nor dropouts occurred during the study time frame, and none of the patients experienced symptom deterioration in response to treatment.
Conclusion: The results suggest that an intensive trauma-focused treatment is a feasible and safe treatment for PTSD patients with clinically elevated symptoms of BPD, and that BPD symptoms decrease along with the PTSD symptoms.
Journal Article
Meta-Analysis with Few Studies and Binary Data: A Bayesian Model Averaging Approach
In meta-analysis, the existence of between-sample heterogeneity introduces model uncertainty, which must be incorporated into the inference. We argue that an alternative way to measure this heterogeneity is by clustering the samples and then determining the posterior probability of the cluster models. The meta-inference is obtained as a mixture of all the meta-inferences for the cluster models, where the mixing distribution is the posterior model probabilities. When there are few studies, the number of cluster configurations is manageable, and the meta-inferences can be drawn with BMA techniques. Although this topic has been relatively neglected in the meta-analysis literature, the inference thus obtained accurately reflects the cluster structure of the samples used. In this paper, illustrative examples are given and analysed, using real binary data.
Journal Article
Trauma reactivation under propranolol among traumatized Syrian refugee children: preliminary evidence regarding efficacy
Background: There is a dearth of therapeutic solutions for traumatized young patients. Trauma reactivation conducted under the influence of the reconsolidation blocker propranolol (Reconsolidation Therapy) is a simple, cost-effective treatment option that has some promising initial results in adults suffering from posttraumatic stress disorder (PTSD).
Objective: To explore the usefulness of this novel treatment in children. The primary outcome was the reduction of PTSD symptoms at the end of treatment, while secondary outcomes included reduction in anxiety and in depressive symptoms.
Method: An open-label clinical trial was conducted in a refugee camp in Syria, investigating the safety and efficacy of this therapeutic strategy in 117 children suffering from enduring PTSD symptoms. Participants received propranolol 90 minutes before briefly recalling (i.e. reactivating) a single personal traumatic memory, for 5 consecutive days. Self-reported anxiety, depressive, and PTSD symptoms were assessed at baseline, as well as 4 and 13 weeks after treatment.
Results: A significant, clinically meaningful symptom reduction was observed at all post-treatment measurement times vs. baseline. More specifically, between baseline and the 13-week follow-up we observed a 64% PTSD symptoms reduction (d = 2.71). In a similar vein, we obtained a 39% symptoms reduction for depressive symptoms (d = 1.01). The general anxiety symptoms improved, but eventually returned to prior level, probably because of the deteriorating living conditions in the camp.
Conclusions: This therapy appeared as a potentially safe and useful treatment strategy for children suffering from PTSD symptoms, warranting replication studies using stronger study designs. The social acceptability and ease of implementation of the treatment should also be noted.
Journal Article
Exploring Medicines Burden Among Adults in New Zealand: A Cross-Sectional Survey
Using medicines regularly can be a burden for some people and can contribute to reduced adherence. In New Zealand, relatively few studies have examined people's medicine-taking experiences and most involved older people, although medicine burden is also an issue for younger people. The UK-developed \"Living with Medicines Questionnaire\" (LMQ-3) is an instrument designed to quantify medicine burden.
The objective was to quantify medicines burden among New Zealand adults, using the LMQ-3, to identify any sub-populations with high medicine burden and to identify specific issues that may need to be addressed.
The study was set in New Zealand and included seven national patient support group websites, and five community pharmacies in Dunedin.
The survey was distributed to adults ≥18 years using ≥ one medicine for ≥3 months. LMQ-3 scores and domain scores were compared by patient characteristics using descriptive statistics and statistical tests.
In total, 472 responses were analysed: 327/417 (78.4%) from patient support group websites and 145/360 (40.3%) from community pharmacies. Most commonly participants were female (295, 62.5%), ≥65 years (236, 50.0%), European (422, 89.4%), retired (232, 49.2%), university educated (203, 43.0%), used medicines independently (449, 95.1%), and paid for prescriptions (429, 90.9%). Most used <10 medicines (415, 87.9%) and
Journal Article
Employment-Related Factors of Forensic Psychiatric Outpatients with Psychotic Disorders
Employment is important for forensic psychiatric patients with psychotic disorders, in terms of reduction in symptoms, improving the quality of life, and preventing re-offenses. However, few detailed studies on employment status in such patients exist. We aimed to determine the employment rate among forensic psychiatric outpatients with psychotic disorders and identify the factors associated with employment.
The study population comprised 406 patients with psychotic disorders who completed a forensic outpatient treatment order, were aged <65 years at discharge from a forensic psychiatric ward and provided written informed consent. Psychotic disorders were defined as psychiatric disorders classified into F2 in the International Statistical Classification of Diseases and Related Health Problems, 10th edition. Demographic data were collected from the medical records of the inpatient treatment period. Prognostic data during the outpatient treatment order period was provided by the reintegration coordinators responsible for coordinating the patients' social environment during this period. Exploratory univariate and multivariable logistic regression analyses identified the factors associated with employment.
The mean age at discharge was 44.4±10.8 years. The mean follow-up period was 2.69±1.01 years. There were 4.6 times more men (n=334) than women (n=72). During the outpatient treatment order period, 56 of 406 participants achieved employment (13.8%). Participants who committed serious crime, including homicide, arson, robbery, and sexual assault, had a lower employment rate compared to participants who committed bodily injury crimes (multivariable odds ratio, 0.421; 95% confidence interval, 0.220-0.807). History of substance use and living with family after discharge from a forensic psychiatric ward positively contributed to employment.
The employment rate among forensic psychiatric outpatients with psychotic disorders was low and was similar to that reported in previous studies on general psychiatric patients with schizophrenia. Furthermore, serious criminal behavior negatively impacted employment.
Journal Article
Social support and posttraumatic growth in a longitudinal study of people living with HIV: the mediating role of positive affect
Background: Psychological research in people living with HIV (PLWH) has been dominated by studies on the negative consequences of HIV infection. However, recently, positive changes following the diagnosis of HIV have been examined, namely the phenomenon of posttraumatic growth (PTG).
Objectives: The aim of this one-year longitudinal study was to investigate the level of PTG and its relationship with social support dimensions (perceived support, need for support, actually received support) and positive and negative affect among PLWH. Specifically, this study explored the mediating role of positive and negative affect in the link between social support and PTG.
Method: Participants filled out the following psychometric tools: Posttraumatic Growth Inventory (PTGI), Berlin Social Support Scales (BSSS) and Positive and Negative Affect Schedule (PANAS-X). Three assessments were performed. Altogether, 129 patients were recruited for the first assessment, 106 patients participated in the second assessment and 82 participants (63.6%) out of the initial sample of 129 participated in all three assessments.
Results: The positive relationship between all examined social support dimensions and PTG was entirely mediated by positive affect. There was no association between negative affect and PTG. Selected socio-medical covariates (sex, employment, higher education, being in a stable relationship and HIV/AIDS status) were related to social support and PTG among participants.
Conclusions: This study points to the need for more research on positive aspects of HIV/AIDS, notably PTG. More specifically, interventions focused on enhancement and sustainment of positive affect among PLWH should be an adjunct to traditional mental health screening among this patient group.
Journal Article
Both stimulatory and inhibitory effects of dietary 5-hydroxytryptophan and tyrosine are found on urinary excretion of serotonin and dopamine in a large human population
Amino acid precursors of dopamine and serotonin have been administered for decades to treat a variety of clinical conditions including depression, anxiety, insomnia, obesity, and a host of other illnesses. Dietary administration of these amino acids is designed to increase dopamine and serotonin levels within the body, particularly the brain. Convincing evidence exists that these precursors normally elevate dopamine and serotonin levels within critical brain tissues and other organs. However, their effects on urinary excretion of neurotransmitters are described in few studies and the results appear equivocal. The purpose of this study was to define, as precisely as possible, the influence of both 5-hydroxytryptophan (5-HTP) and tyrosine on urinary excretion of serotonin and dopamine in a large human population consuming both 5-HTP and tyrosine. Curiously, only 5-HTP exhibited a marginal stimulatory influence on urinary serotonin excretion when 5-HTP doses were compared to urinary serotonin excretion; however, a robust relationship was observed when alterations in 5-HTP dose were compared to alterations in urinary serotonin excretion in individual patients. The data indicate three statistically discernible components to 5-HTP responses, including inverse, direct, and no relationships between urinary serotonin excretion and 5-HTP doses. The response to tyrosine was more consistent but primarily yielded an unexpected reduction in urinary dopamine excretion. These data indicate that the urinary excretion pattern of neurotransmitters after consumption of their precursors is far more complex than previously appreciated. These data on urinary neurotransmitter excretion might be relevant to understanding the effects of the precursors in other organs.
Journal Article
Applied Geropsychology
This chapter contains sections titled:
Key Issues in Applied Geropsychology
Assessment
Behavioral Interventions
Prevention and Promotion
Caregiving
Concluding Remarks
References
Book Chapter
Observers
This chapter contains sections titled:
Biases in judgements of sport performance
Predictions and betting
Summary
Book Chapter