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Recent changes to US research funding are having far-reaching consequences that imperil the integrity of science and the provision of care to vulnerable populations. Resisting these changes, the BJPsych Portfolio reaffirms its commitment to publishing mental science and advancing psychiatric knowledge that improves the mental health of one and all.
When using machine learning to model environmental systems, it is often a model’s ability to predict extreme behaviors that yields the highest practical value to policy makers. However, most existing error metrics used to evaluate the performance of environmental machine learning models weigh error equally across test data. Thus, routine performance is prioritized over a model’s ability to robustly quantify extreme behaviors. In this work, we present a new error metric, termed Reflective Error, which quantifies the degree at which our model error is distributed around our extremes, in contrast to existing model evaluation methods that aggregate error over all events. The suitability of our proposed metric is demonstrated on a real-world hydrological modeling problem, where extreme values are of particular concern.
Machine learning models have been used extensively in hydrology, but issues persist with regard to their transparency, and there is currently no identifiable best practice for forcing variables in streamflow or flood modeling. In this paper, using data from the Centre for Ecology & Hydrology’s National River Flow Archive and from the European Centre for Medium-Range Weather Forecasts, we present a study that focuses on the input variable set for a neural network streamflow model to demonstrate how certain variables can be internalized, leading to a compressed feature set. By highlighting this capability to learn effectively using proxy variables, we demonstrate a more transferable framework that minimizes sensing requirements and that enables a route toward generalizing models.
In difficult-to-treat depression (DTD) the outcome metrics historically used to evaluate treatment effectiveness may be suboptimal. Metrics based on remission status and on single end-point (SEP) assessment may be problematic given infrequent symptom remission, temporal instability, and poor durability of benefit in DTD.
Methods
Self-report and clinician assessment of depression symptom severity were regularly obtained over a 2-year period in a chronic and highly treatment-resistant registry sample (N = 406) receiving treatment as usual, with or without vagus nerve stimulation. Twenty alternative metrics for characterizing symptomatic improvement were evaluated, contrasting SEP metrics with integrative (INT) metrics that aggregated information over time. Metrics were compared in effect size and discriminating power when contrasting groups that did (N = 153) and did not (N = 253) achieve a threshold level of improvement in end-point quality-of-life (QoL) scores, and in their association with continuous QoL scores.
Results
Metrics based on remission status had smaller effect size and poorer discrimination of the binary QoL outcome and weaker associations with the continuous end-point QoL scores than metrics based on partial response or response. The metrics with the strongest performance characteristics were the SEP measure of percentage change in symptom severity and the INT metric quantifying the proportion of the observation period in partial response or better. Both metrics contributed independent variance when predicting end-point QoL scores.
Conclusions
Revision is needed in the metrics used to quantify symptomatic change in DTD with consideration of INT time-based measures as primary or secondary outcomes. Metrics based on remission status may not be useful.
Approximately one-third of individuals in a major depressive episode will not achieve sustained remission despite multiple, well-delivered treatments. These patients experience prolonged suffering and disproportionately utilize mental and general health care resources. The recently proposed clinical heuristic of ‘difficult-to-treat depression’ (DTD) aims to broaden our understanding and focus attention on the identification, clinical management, treatment selection, and outcomes of such individuals. Clinical trial methodologies developed to detect short-term therapeutic effects in treatment-responsive populations may not be appropriate in DTD. This report reviews three essential challenges for clinical intervention research in DTD: (1) how to define and subtype this heterogeneous group of patients; (2) how, when, and by what methods to select, acquire, compile, and interpret clinically meaningful outcome metrics; and (3) how to choose among alternative clinical trial design options to promote causal inference and generalizability. The boundaries of DTD are uncertain, and an evidence-based taxonomy and reliable assessment tools are preconditions for clinical research and subtyping. Traditional outcome metrics in treatment-responsive depression may not apply to DTD, as they largely reflect the only short-term symptomatic change and do not incorporate durability of benefit, side effect burden, or sustained impact on quality of life or daily function. The trial methodology will also require modification as trials will likely be of longer duration to examine the sustained impact, raising complex issues regarding control group selection, blinding and its integrity, and concomitant treatments.
Strong associations between neural tube defects (NTDs) and monozygotic (MZ) twinning have long been noted, and it has been suggested that NTD cases who do not present as MZ twins may be the survivors of MZ twinning events. We have recently shown that MZ twins carry a strong, distinctive DNA methylation signature and have developed an algorithm based on genomewide DNA methylation array data that distinguishes MZ twins from dizygotic twins and other relatives at well above chance level. We have applied this algorithm to published methylation data from five fetal tissues (placental chorionic villi, kidney, spinal cord, brain and muscle) collected from spina bifida cases (n = 22), anencephalic cases (n = 15) and controls (n = 19). We see no difference in signature between cases and controls, providing no support for a common etiological role of MZ twinning in NTDs. The strong associations therefore continue to await elucidation.
To evaluate broad-spectrum intravenous antibiotic use before and after the implementation of a revised febrile neutropenia management algorithm in a population of adults with hematologic malignancies.
Design:
Quasi-experimental study.
Setting and population:
Patients admitted between 2014 and 2018 to the Adult Malignant Hematology service of an acute-care hospital in the United States.
Methods:
Aggregate data for adult malignant hematology service were obtained for population-level antibiotic use: days of therapy (DOT), C. difficile infections, bacterial bloodstream infections, intensive care unit (ICU) length of stay, and in-hospital mortality. All rates are reported per 1,000 patient days before the implementation of an febrile neutropenia management algorithm (July 2014–May 2016) and after the intervention (June 2016–December 2018). These data were compared using interrupted time series analysis.
Results:
In total, 2,014 patients comprised 6,788 encounters and 89,612 patient days during the study period. Broad-spectrum intravenous (IV) antibiotic use decreased by 5.7% with immediate reductions in meropenem and vancomycin use by 22 (P = .02) and 15 (P = .001) DOT per 1,000 patient days, respectively. Bacterial bloodstream infection rates significantly increased following algorithm implementation. No differences were observed in the use of other antibiotics or safety outcomes including C. difficile infection, ICU length of stay, and in-hospital mortality.
Conclusions:
Reductions in vancomycin and meropenem were observed following the implementation of a more stringent febrile neutropenia management algorithm, without evidence of adverse outcomes. Successful implementation occurred through a collaborative effort and continues to be a core reinforcement strategy at our institution. Future studies evaluating patient-level data may identify further stewardship opportunities in this population.
In 2008, we saw an emerging business need to accurately identify and develop individuals early in their careers who have the potential to be effective leaders in later organizational positions. We decided early on to take a comprehensive and systematic approach to the challenge in order to build effective solutions with real organizational impact that are sustainable over time. We knew that this was a complex problem and that there was little agreement in industrial–organizational (I-O) psychology on how to approach this critical business need and what approaches would be most effective. Since then, we moved through the following process stages to arrive at effective solutions that are now being used in numerous organizations.
The past four decades have witnessed a transformation in research on thebenefits of psychological therapies. However, even though therapistshighlight that negative and adverse effects are seen in day-to-day practice,research on the negative effects of psychotherapy is insufficient. Given theunrelenting popularity of therapies, the argument for examining the adverseeffects of psychotherapy would seem to be compelling. Such a strategy wouldextend beyond supervision of individual therapists to the introduction ofmonitoring systems that allow for a more systematic examination of failedpsychotherapy interventions (such as exist for medication prescribing). Thestarting point could be the development of a consensus on how to define,classify and assess psychotherapy side-effects, unwanted events, adversereactions, etc. This would provide a conceptual framework for communication,monitoring and research. This approach should not be viewed as an attack ontherapies: every branch of medicine learns from mistakes, the same mustsurely be true for psychological treatments.
Few studies have investigated developmental strengths and weaknesses within the cognitive profile of children and adolescents with fragile X syndrome (FXS), a single-gene cause of inherited intellectual impairment. With a prospective longitudinal design and using normalized raw scores (Z scores) to circumvent floor effects, we measured cognitive functioning of 184 children and adolescents with FXS (ages 6 to 16) using the Wechsler Scale of Intelligence for Children on one to three occasions for each participant. Participants with FXS received lower raw scores relative to the Wechsler Scale of Intelligence for Children normative sample across the developmental period. Verbal comprehension, perceptual organization, and processing speed Z scores were marked by a widening gap from the normative sample, while freedom from distractibility Z scores showed a narrowing gap. Key findings include a relative strength for verbal skills in comparison with visuospatial–constructive skills arising in adolescence and a discrepancy between working memory (weakness) and processing speed (strength) in childhood that diminishes in adolescence. Results suggest that the cognitive profile associated with FXS develops dynamically from childhood to adolescence. Findings are discussed within the context of aberrant brain morphology in childhood and maturation in adolescence. We argue that assessing disorder-specific cognitive developmental profiles will benefit future disorder-specific treatment research.
Fragile-X syndrome (FXS) is a neurodevelopmental disorder associated with intellectual disability and neurobiological abnormalities including white matter microstructural differences. White matter differences have been found relative to neurotypical individuals.
Aims
To examine whether FXS white matter differences are related specifically to FXS or more generally to the presence of intellectual disability.
Method
We used voxel-based and tract-based analytic approaches to compare individuals with FXS (n = 40) with gender- and IQ-matched controls (n = 30).
Results
Individuals with FXS had increased fractional anisotropy and decreased radial diffusivity values compared with IQ-matched controls in the inferior longitudinal, inferior fronto-occipital and uncinate fasciculi.
Conclusions
The genetic variation associated with FXS affects white matter microstructure independently of overall IQ. White matter differences, found in FXS relative to IQ-matched controls, are distinct from reported differences relative to neurotypical controls. This underscores the need to consider cognitive ability differences when investigating white matter microstructure in neurodevelopmental disorders.
The Royal College of Psychiatrists' Committee on Electroconvulsive Therapy (ECT) and Related Treatments advises the measurement of initial seizure threshold in all patients undergoing ECT if possible. The subconvulsive electrical stimulation inherent in this process is thought to increase the risk of bradycardia and therefore asystole. Our aim was to establish the prevalence of asystole (no heart beat for 5 or more seconds) during empirical measurement of seizure threshold in patients who had not received anticholinergic drugs, as we were unable to find any published reports of bradycardia or asystole prevalence under these conditions. The electrocardiogram traces of 50 such consecutive patients were analysed later.
Results
Asystole occurred in 5% of stimulations. Each episode of asystole resolved spontaneously with no adverse outcomes. Contrary to expectations, asystole was no more prevalent in subconvulsive stimulations than in convulsive stimulations.
Clinical implications
There was no evidence that the empirical measurement of the seizure threshold added to the cardiovascular risk of ECT.
Despite more than a decade of heightened defence spending and active fighting in the War in Afghanistan, the longest combat operation in the history of the Canadian Forces, scholars know precious little about how the socio-demographic characteristics and attitudes of Canadians may influence their views about taking part in overseas combat operations and funding the institution charged with carrying out these dangerous activities. By testing a range of hypotheses, which purport to explain the influence of multiple socio-demographic and attitudinal factors on Canadians' attitudes toward defence spending and the participation of the Canadian Forces in overseas combat operations, against data from the 2004 and 2011 Canadian Election Study, this article ascertains the most important determinants of Canadians' preferences about defence spending and the use of military force by the Government of Canada.
It is important to evaluate any patient's response to any treatment. This is especially the case for an emotive and serious intervention such as ECT. This chapter will offer advice on evaluating response, in terms of the relief of the patient's psychiatric symptoms, monitoring seizures in the ECT clinic and assessing the cognitive effects of ECT.
Establishing a baseline
It is necessary to quantify the severity of the patient's symptoms before starting treatment. Assessments should be undertaken by the referring team before, during and after the course of treatment.
Disease symptoms
Depression is the most common indication for ECT. The Montgomery– Åsberg Depression Rating Scale (MADRS) (Montgomery & Åsberg, 1979) has been widely used for assessing auditing response to ECT. It has been found to be acceptable to both patients and practitioners and is recommended for routine use. The Hamilton Rating Scale for Depression (Hamilton, 1960), which has often been used in research, would be an alternative. For patients receiving ECT for other indications such as mania or catatonia, the Brief Psychiatric Rating Scale (BPRS) (Lukoff et al, 1986) or Global Assessment of Functioning (GAF) (Piersma & Boes, 1997) could be considered. Whatever the indication for treatment is, a baseline level of severity on the Clinical Global Impression of Severity (CGI-S) (Guy & Bonato, 1976) should be documented before the course starts (Box 6.1).
Cognition
Before starting a course of ECT, the patient's level of functioning in memory, verbal and non-verbal cognitive domains should be established. Most patients starting a course of ECT will be severely ill. They may be reluctant or unable to participate in detailed neuropsychological assessment. Most UK clinics use the MMSE (Folstein et al, 1975). This is not an entirely satisfactory instrument, but it has the advantage that most clinical staff are familiar with its use. It is suggested that clinics continue to use the MMSE until it is demonstrated that a better alternative exists. Practitioners should be aware that the MMSE is copyright and that there may be clinically relevant cognitive impairment which the MMSE cannot detect (see Chapter 8).
By
Gerard J. Allan, Department of Biological Sciences, Northern Arizona University,
Stephen M. Shuster, Department of Biological Sciences, Northern Arizona University,
Scott Woolbright, The Institute for Genomic Biology, University of Illinois,
Faith Walker, Department of Biological Sciences, Northern Arizona University,
Nashelly Meneses, Department of Biological Sciences, Northern Arizona University,
Arthur Keith, Department of Biological Sciences, Northern Arizona University,
Joseph K. Bailey, Department of Ecology and Evolutionary Biology, University of Tennessee,
Thomas G. Whitham, Department of Biological Sciences, Northern Arizona University
Trait-mediated indirect interactions (TMIIs) are important mediators of community diversity and structure and associated ecosystem processes. Elucidating the genetic basis of ecologically important phenotypic traits is the first step toward understanding the complex interactions that occur among community members. Molecular markers routinely used in quantitative trait loci (QTL) analyses (e.g., amplified fragment length polymorphisms (AFLPs), simple sequence repeats (SSRs)) have provided researchers with a toolbox for investigating the genetic basis of heritable traits. A goal of this research is to link genetically based traits to community interactions and ecosystem function. Ultimately, this insight can open a window onto the evolutionary dynamics that shape community structure and associated ecosystem processes (e.g., nutrient cycling). Such an approach is important as it bears on the continued development of the field of community genetics, which seeks to understand the genetic interactions that occur between species and their abiotic environment in complex communities (e.g., Whitham et al. 2003, 2006; Johnson and Agrawal 2005; LeRoy et al. 2006; Bangert et al. 2006a, b; Schweitzer et al. 2008; Crutsinger et al. 2009; Bailey et al. 2009).
WORCESTER is the best evidenced of all the early Anglo-Saxon bishoprics, with a substantial collection of material on which to construct narratives. yet this has rarely been done, perhaps because of the difficulty of ascertaining which charters are reliable. This is a pity, for Worcester is unparalleled in the opportunities it presents to scholars seeking to understand the development of a church and its relationship with its landscape. The way in which the bishops of Worcester built up the power of their church can be at least dimly discerned in this material, and the effort of determining how the bishops did this and in what circumstances is worthwhile, as it presents an alternative perspective on parts of Anglo-Saxon history where existing narratives are focused on secular leaders, not churchmen.
A key problem with studying the early bishops of Worcester is that they are faceless historical individuals; unlike the other subjects of this volume, the predecessors of Bishop Wærfrith (see Table 4.1) have not left a legacy of writings or controversies but, at most, a few charters which, in the current state of knowledge, may tell us more about the donors than the bishops. Understanding individual bishops' roles in history and contextualizing their few identifiable actions is, therefore, nigh on impossible. But this is not to say that there is nothing to be gained through study of those who led the episcopal church of Worcester through its first two centuries: what might appear as isolated and unconnected facts about members of the Worcester episcopate can, when the bishops are studied as a group, reveal interesting patterns.
The genetic basis of cardiovascular disease (CVD) is complex and still largely elusive. Plasma lipid concentrations are well-established risk factors for cardiovascular disease (CVD), and have adult heritabilities ranging from 0.48 to 0.87. Estimates for adolescents are slightly higher (range 0.71 to 0.82). To identify loci affecting lipid concentrations across adolescence, we analyzed longitudinal lipid data in a sample of 134 monozygotic and 626 dizygotic twin pairs at ages twelve, fourteen and sixteen, and their siblings, from 760 Australian families. Univariate linkage analysis for each phenotype and time point was supplemented by multivariate analysis across the time points. A genome-wide association scan was also performed on a subset of the subjects (N = 441). The strongest linkage was seen for triglycerides on chromosome 6p24.3 (multivariate –log10p = 6.81; equivalent LOD = 6.13; p = 1.55 × 10–7). Significant linkage was also found for LDL cholesterol on chromosome 2q35 (multivariate –log10p = 5.59; equivalent LOD = 4.53; p = 2.57 × 10–6). In the association analysis, rs10503840 on 8p21.1 was significantly associated with total cholesterol levels at age fourteen (p = 8.24 × 10–7, estimated significance threshold 2.45 × 10–6). Association at p < 2.25 × 10–6 was also found between triglycerides at age 12 and rs10507266, in an intron of THRAP2 (MIM 608771) on 12q24.21; and between HDL-C at age 14 and rs10506325 in an intergenic region of 12q13.13. Suggestive evidence of association at ages twelve and fourteen was found between HDL-C and rs10492859 on 16q23 (p = 2.42 × 10–5 and 2.77 × 10–4, respectively). Further longitudinal genetic studies of cardiovascular risk factors, focused on critical periods of development or change, are needed.