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Patients with posttraumatic stress disorder (PTSD) exhibit smaller regional brain volumes in commonly reported regions including the amygdala and hippocampus, regions associated with fear and memory processing. In the current study, we have conducted a voxel-based morphometry (VBM) meta-analysis using whole-brain statistical maps with neuroimaging data from the ENIGMA-PGC PTSD working group.
Methods
T1-weighted structural neuroimaging scans from 36 cohorts (PTSD n = 1309; controls n = 2198) were processed using a standardized VBM pipeline (ENIGMA-VBM tool). We meta-analyzed the resulting statistical maps for voxel-wise differences in gray matter (GM) and white matter (WM) volumes between PTSD patients and controls, performed subgroup analyses considering the trauma exposure of the controls, and examined associations between regional brain volumes and clinical variables including PTSD (CAPS-4/5, PCL-5) and depression severity (BDI-II, PHQ-9).
Results
PTSD patients exhibited smaller GM volumes across the frontal and temporal lobes, and cerebellum, with the most significant effect in the left cerebellum (Hedges’ g = 0.22, pcorrected = .001), and smaller cerebellar WM volume (peak Hedges’ g = 0.14, pcorrected = .008). We observed similar regional differences when comparing patients to trauma-exposed controls, suggesting these structural abnormalities may be specific to PTSD. Regression analyses revealed PTSD severity was negatively associated with GM volumes within the cerebellum (pcorrected = .003), while depression severity was negatively associated with GM volumes within the cerebellum and superior frontal gyrus in patients (pcorrected = .001).
Conclusions
PTSD patients exhibited widespread, regional differences in brain volumes where greater regional deficits appeared to reflect more severe symptoms. Our findings add to the growing literature implicating the cerebellum in PTSD psychopathology.
Posttraumatic stress disorder (PTSD) has been associated with advanced epigenetic age cross-sectionally, but the association between these variables over time is unclear. This study conducted meta-analyses to test whether new-onset PTSD diagnosis and changes in PTSD symptom severity over time were associated with changes in two metrics of epigenetic aging over two time points.
Methods
We conducted meta-analyses of the association between change in PTSD diagnosis and symptom severity and change in epigenetic age acceleration/deceleration (age-adjusted DNA methylation age residuals as per the Horvath and GrimAge metrics) using data from 7 military and civilian cohorts participating in the Psychiatric Genomics Consortium PTSD Epigenetics Workgroup (total N = 1,367).
Results
Meta-analysis revealed that the interaction between Time 1 (T1) Horvath age residuals and new-onset PTSD over time was significantly associated with Horvath age residuals at T2 (meta β = 0.16, meta p = 0.02, p-adj = 0.03). The interaction between T1 Horvath age residuals and changes in PTSD symptom severity over time was significantly related to Horvath age residuals at T2 (meta β = 0.24, meta p = 0.05). No associations were observed for GrimAge residuals.
Conclusions
Results indicated that individuals who developed new-onset PTSD or showed increased PTSD symptom severity over time evidenced greater epigenetic age acceleration at follow-up than would be expected based on baseline age acceleration. This suggests that PTSD may accelerate biological aging over time and highlights the need for intervention studies to determine if PTSD treatment has a beneficial effect on the aging methylome.
This case provides a complete overview of shoulder dystocia through a case-based learning approach. A shoulder dystocia scenario is presented with history of present illness and physical exam details outlined. An example of how to optimally manage the case is provided. Shoulder dystocia diagnosis, epidemiology, and fetal and maternal risk factors and complications are reviewed. Systematic maneuvers to relieve shoulder dystocia are explained and post-delivery best practices are discussed. A comprehensive shoulder dystocia management algorithm is proposed.
The current method used by the US Government to calculate benefits and costs does not accurately measure the monetary value of some regulations. The problem is that the method fails to recognize the possibility that individual valuations, reflecting judgments in a relatively isolated, uncoordinated situation, might be significantly different from individual valuations in a situation of coordination. For example, people might be willing to pay $X for a good, supposing that other people have that good, but might be willing to pay $Y to abolish that good, supposing that no one will have that good. Or people might be willing to pay $X to protect members of an endangered species in their individual capacity, but far more than $X for the same purpose, assuming that many others are paying as well; one reason may be that an individual expenditure seems futile. We sketch, identify, and explain this unmeasured value, which we define as coordination value, meant as an umbrella concept to cover several categories of cases in which individual valuation measured in the uncoordinated state might be inadequate. Changing the methodology of benefit–cost analysis to consider coordination value would present serious empirical challenges, but would eliminate the estimation error.
Understanding firn densification is essential for interpreting ice core records, predicting ice sheet mass balance, elevation changes and future sea-level rise. Current models of firn densification on the Antarctic ice sheet (AIS), such as the Herron and Langway (1980) model are either simple semi-empirical models that rely on sparse climatic data and surface density observations or complex physics-based models that rely on poorly understood physics. In this work, we introduce a deep learning technique to study firn densification on the AIS. Our model, FirnLearn, evaluated on 225 cores, shows an average root-mean-square error of 31 kg m−3 and explained variance of 91%. We use the model to generate surface density and the depths to the $550\,\mathrm{kg\,m}^{-3}$ and $830\,\mathrm{kg\,m}^{-3}$ density horizons across the AIS to assess spatial variability. Comparisons with the Herron and Langway (1980) model at ten locations with different climate conditions demonstrate that FirnLearn more accurately predicts density profiles in the second stage of densification and complete density profiles without direct surface density observations. This work establishes deep learning as a promising tool for understanding firn processes and advancing towards a universally applicable firn model.
Fasedienol (PH94B; 3β-androsta-4,16-dien-3-ol) is a synthetic neuroactive nasal spray from the androstane family of pherines. Intranasal fasedienol activates receptors in peripheral nasal chemosensory neurons connected to subsets of neurons in the olfactory bulbs that in turn are neurally connected to neurons in the limbic amygdala involved in the pathophysiology of SAD and potentially other anxiety and mood disorders. Fasedienol is locally metabolized in the olfactory mucosa without systemic uptake or binding to CNS receptors. The objective of the present study was to compare fasedienol vs. placebo during a public speaking challenge in subjects with SAD.
Methods
This was a multi-center, double-blind, randomized, placebo-controlled study (NCT05011396). After screening (Visit 1), all subjects completed Visit 2 (V2, Baseline, placebo nasal spray administered to all subjects) and participated in a 5-minute public speaking challenge (PSC) during which Subjective Units of Distress Scores (SUDS) were recorded. Subjects with SUDS >= to 70 were invited back a week later for the Visit 3 (V3) treatment visit and randomly allocated to receive either fasedienol (3.2 μg intranasally) or placebo, then undergo a second 5-minute PSC, with SUDS scores recorded. After the V3 PSC, subjects completed a Patient Global Impression of Change (PGI-C) and trained raters completed a Clinical Global Impression of Improvement (CGI-I). CGI-I responders were defined as those assigned scores of 1 (very much improved) or 2 (much improved); PGI-C responders reported scores of 1 (very much less anxious) or 2 (much less anxious). ANCOVA with baseline SUDS as a covariate was used to compare change in mean SUDS from V2 to V3 for the subjects administered fasedienol at V3 vs those who received placebo at V3.
Results
Fasedienol-treated patients (n=70) demonstrated a statistically significant greater change in mean SUDS score (least-squares (LS) mean = -13.8) compared with placebo (n=71, LS mean = -8.0), for a difference between groups of -5.8 (p=0.015). The proportion of CGI-I responders was higher in the fasedienol group 37.7% vs. placebo 21.4% (p=0.033), as was the proportion of PGI-C responders: fasedienol 40.6% vs. placebo 18.6% (p=0.003). Fasedienol was well-tolerated with no treatment-emergent adverse events above 1.5% occurrence.
Conclusion
The Phase 3 PALISADE-2 trial results demonstrated that a single dose of fasedienol prior to a stressful PSC produced efficacy on patient-rated SUDS and PGI-C, as well as the clinician-rated CGI-I. The results also confirmed the nasal-amygdala neural circuits as a new portal for administration of pharmaceuticals. The data support continued development of fasedienol as a first-in-class, rapid-onset, well-tolerated treatment option for SAD without addictive properties.
Exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), an environmental endocrine disruptor and model AhR agonist, is linked to skeletal abnormalities, cardiac edema, stunted growth rate, altered metabolism, and neurobehavioral deficits. We have previously reported transgenerational reproductive outcomes of developmental TCDD exposure in adult zebrafish (Danio rerio), an NIH-validated model for developmental and generational toxicology. Using the same paradigm of sublethal TCDD exposure (50 pg/ml) at both 3 and 7 weeks post fertilization (wpf), we investigated several novel endpoints, including longitudinal morphometrics and anxiety-linked behavior, in fish exposed as juveniles. We also assessed developmental abnormalities and neurobehavior in their F1 larval offspring. TCDD exposure induced timepoint-dependent decreases in several craniofacial and trunk morphometrics across juvenile development. In early adulthood, however, only exposed males underwent a transient period of compensatory growth, ending between 7 and 12 months post fertilization (mpf). At 12 mpf, exposed adult fish of both sexes displayed increased exploratory behaviors in a novel tank test. The F1 offspring of parents exposed at both 3 and 7 wpf were hyperactive, but neurobehavioral outcomes diverged depending on parental exposure window. F1 exposure-lineage larvae had increased rates of edema and skeletal abnormalities, but fewer unhatched larvae compared to controls. Parent- and timepoint-specific effects of exposure on abnormality rate were also evaluated; these outcomes were considerably less severe. Our novel behavioral findings expand current knowledge of the long-term and intergenerational consequences of early-life TCDD exposure in a zebrafish model, in addition to delineating minor longitudinal morphometric changes in exposed fish and abnormalities in larval offspring.
Amid resurgent geopolitical fissures and in the aftermath of the Covid-19 pandemic, there is a growing awareness in the sector of the need for, and concern about, national and international collaboration in archaeological projects. This article reflects on present-day challenges for international collaboration in central Eurasian archaeology and furthers a much-needed discussion about (re)integrating local narratives with inter-regional trends in future research. Responsible and practical proposals for bridging collaborator differences in institutional or publishing obligations, language capacities and access to resources are discussed.
OBJECTIVES/GOALS: Contingency management (CM) procedures yield measurable reductions in cocaine use. This poster describes a trial aimed at using CM as a vehicle to show the biopsychosocial health benefits of reduced use, rather than total abstinence, the currently accepted metric for treatment efficacy. METHODS/STUDY POPULATION: In this 12-week, randomized controlled trial, CM was used to reduce cocaine use and evaluate associated improvements in cardiovascular, immune, and psychosocial well-being. Adults aged 18 and older who sought treatment for cocaine use (N=127) were randomized into three groups in a 1:1:1 ratio: High Value ($55) or Low Value ($13) CM incentives for cocaine-negative urine samples or a non-contingent control group. They completed outpatient sessions three days per week across the 12-week intervention period, totaling 36 clinic visits and four post-treatment follow-up visits. During each visit, participants provided observed urine samples and completed several assays of biopsychosocial health. RESULTS/ANTICIPATED RESULTS: Preliminary findings from generalized linear mixed effect modeling demonstrate the feasibility of the CM platform. Abstinence rates from cocaine use were significantly greater in the High Value group (47% negative; OR = 2.80; p = 0.01) relative to the Low Value (23% negative) and Control groups (24% negative;). In the planned primary analysis, the level of cocaine use reduction based on cocaine-negative urine samples will serve as the primary predictor of cardiovascular (e.g., endothelin-1 levels), immune (e.g., IL-10 levels) and psychosocial (e.g., Addiction Severity Index) outcomes using results from the fitted models. DISCUSSION/SIGNIFICANCE: This research will advance the field by prospectively and comprehensively demonstrating the beneficial effects of reduced cocaine use. These outcomes can, in turn, support the adoption of reduced cocaine use as a viable alternative endpoint in cocaine treatment trials.
Attention-deficit/hyperactivity disorder (ADHD) symptoms are associated with myriad adverse outcomes, including interpersonal difficulties, but factors that moderate the developmental course and functional impact of ADHD over time are not well understood. The present study evaluated developmental contributions of the triarchic neurobehavioral traits (boldness, meanness, and disinhibition) to ADHD symptomatology and its subdimensions from adolescence to young adulthood. Participants were twins and triplets assessed at ages 14, 17, and 19 (initial N = 1,185, 51.2% female). Path analyses using negative binomial regression revealed that boldness at age 14 was associated with more ADHD symptoms cross-sectionally (especially hyperactivity/impulsivity), but fewer symptoms (especially inattention) at age 19 in the prospective analysis. Notably, inclusion of interpersonal problems at ages 14 and 17 as covariates reduced the latter effect to nonsignificant. Disinhibition concurrently and prospectively predicted higher levels of ADHD symptoms, including both subdimensions, and the prospective effects were partially mediated by greater social impairment at age 17. Meanness prospectively (but not concurrently) predicted higher levels of hyperactivity/impulsivity symptoms. Sex moderated certain associations of meanness and disinhibition with ADHD symptoms. These findings highlight how fundamental neurobehavioral traits shape both psychopathology and adaptive outcomes in the developmental course of ADHD.
The Eighth World Congress of Pediatric Cardiology and Cardiac Surgery (WCPCCS) will be held in Washington DC, USA, from Saturday, 26 August, 2023 to Friday, 1 September, 2023, inclusive. The Eighth World Congress of Pediatric Cardiology and Cardiac Surgery will be the largest and most comprehensive scientific meeting dedicated to paediatric and congenital cardiac care ever held. At the time of the writing of this manuscript, The Eighth World Congress of Pediatric Cardiology and Cardiac Surgery has 5,037 registered attendees (and rising) from 117 countries, a truly diverse and international faculty of over 925 individuals from 89 countries, over 2,000 individual abstracts and poster presenters from 101 countries, and a Best Abstract Competition featuring 153 oral abstracts from 34 countries. For information about the Eighth World Congress of Pediatric Cardiology and Cardiac Surgery, please visit the following website: [www.WCPCCS2023.org]. The purpose of this manuscript is to review the activities related to global health and advocacy that will occur at the Eighth World Congress of Pediatric Cardiology and Cardiac Surgery.
Acknowledging the need for urgent change, we wanted to take the opportunity to bring a common voice to the global community and issue the Washington DC WCPCCS Call to Action on Addressing the Global Burden of Pediatric and Congenital Heart Diseases. A copy of this Washington DC WCPCCS Call to Action is provided in the Appendix of this manuscript. This Washington DC WCPCCS Call to Action is an initiative aimed at increasing awareness of the global burden, promoting the development of sustainable care systems, and improving access to high quality and equitable healthcare for children with heart disease as well as adults with congenital heart disease worldwide.
The retreat of settlement, which began generally in England in the early 14th century and which gathered momentum after successive outbreaks of plague, has frequently been associated with the abandonment of marginal lands. As the pressure of population eased off, as the relative land shortage of the 13th century gave way to a relative land surplus in the 14th century, “there followed a retreat from the marginal lands” and “infertile farms were abandoned in favour of the more rewarding farms elsewhere”. Attempts to explain this retreat have invoked soil exhaustion and climatic changes in addition to an easing of the pressure of population upon land but, whatever the causes, it is invariably suggested that marginal land, or as M. W. Beresford has called it “half-wanted land”, was the first to be abandoned. This paper aims to examine the contracting arable lands of Bedfordshire in relation to edaphic and topographic conditions within the county.
An opportunity to probe this relationship in 1341 is afforded by the Inquisitiones Nonarum, which relate to a grant by Parliament to Edward III in 1342, to assist him in his wars, of one-ninth of the value of corn, wool and lambs produced in the realm. The value of these items was assessed, parish by parish, from the evidence given by groups of parishioners upon oath. Since the ninth was assessed after the tithe had been taken, it was in fact one-ninth of nine-tenths of the total value of lay agricultural production and therefore identical with the tithe of these three items (corn, wool and lambs). As a guide, therefore, the jurors who compiled the parish returns had before them an assessment of one-tenth of clerical incomes in 1291. The parishioners were required to explain the discrepancy between the older and newer values. Discrepancy there inevitably was, for clerical incomes included more than the tithe of corn, wool and lambs: there was, in addition, the value of the glebe and monastic holdings, the revenue from the small tithes of cider, flax, hemp, pigs, geese and poultry, together with oblations, mortuary fees, and other items.
Surgically implanted vagus nerve stimulation (VNS) is a recognised treatment for depression. The vagus nerve can also be stimulated non-invasively via its auricular branch, using transauricular vagus nerve stimulation (taVNS). Heart rate variability (HRV) is a putative biomarker of autonomic nervous system (ANS) engagement. We aimed to test the impact of taVNS on the ANS of healthy volunteers by measuring HRV using a double-blind, sham-controlled, longitudinal design to acquire data over 7 days using wearable cardiac sensors.
Methods
taVNS was delivered to the left ear of healthy volunteers using a transcutaneous electrical nerve stimulation (TENS) device via a custom clip electrode (developed at Newcastle University). All participants were stimulated at 10 Hz, with pulse widths of 300 ms and variable current outputs, depending on perceptual thresholds. We delivered double-blinded active and sham taVNS for hour-long periods, in the morning and evening. We also recorded an electrocardiogram (ECG) lead I using a VitalPatch for 7 consecutive days. Python scripts were developed to produce HRV timeseries and plot data. ECG frequency domain parameters – low- (LF) (0.05–0.15 Hz) and high-frequency (HF) power (0.15–0.4 Hz) – were calculated for each stimulation period. The LF/HF ratio was used as a marker of autonomic modulation. The Wilcoxon signed-rank test was used to compare LF/HF ratio distributions.
Results
Initial data from the wearable sensors were used to develop interpolation scripts to improve the processing of noise, missed R waves and ectopic beats, to reduce errors when estimating HRV from the heart rate signal. Initial results from 97 individual 1-hour long stimulation periods, from 18 participants, show that active stimulation in the morning, when compared with sham stimulation in the same period, significantly reduces the LF/HF ratio. The median and interquartile range (IQR) of the LF/HF ratio for the active and sham periods was, respectively, 1.72 (1.99) and 2.75 (2.82), a statistically significant difference (p = 0.043).
Conclusion
taVNS modulates HRV frequency domains, suggestive of vagal cardiac effects, and replicates findings from previous taVNS studies. Reductions in the LF/HF ratio are suggestive of increased parasympathetic tone. As the auricular branch of the vagus does not have any direct cardiac efferents, this suggests central ANS modulation using taVNS. Secondly, it suggests that cardiac ANS modulation could be used as a proxy measure of afferent vagal stimulation, which could be of clinical utility. These effects warrant exploration in a larger cohort study, including wider demographics (including age range) and improved processing pipelines.
To investigate changes in neuroregenerative pathways with vocal fold denervation in response to vocal fold augmentation.
Methods
Eighteen Yorkshire crossbreed swine underwent left recurrent laryngeal nerve transection, followed by observation or augmentation with carboxymethylcellulose or calcium hydroxyapatite at two weeks. Polymerase chain reaction expression of genes regulating muscle growth (MyoD1, MyoG and FoxO1) and atrophy (FBXO32) were analysed at 4 and 12 weeks post-injection. Thyroarytenoid neuromuscular junction density was quantified using immunohistochemistry.
Results
Denervated vocal folds demonstrated reduced expression of MyoD1, MyoG, FoxO1 and FBXO32, but overexpression after augmentation. Healthy vocal folds showed increased early and late MyoD1, MyoG, FoxO1 and FBXO32 expression in all animals. Neuromuscular junction density had a slower decline in augmented compared to untreated denervated vocal folds, and was significantly reduced in healthy vocal folds contralateral to augmentation.
Conclusion
Injection augmentation may slow neuromuscular degeneration pathways in denervated vocal folds and reduce compensatory remodelling in contralateral healthy vocal folds.
Background: The Canadian Registry for Amyloidosis Research (CRAR) is a nationwide disease registry of transthyretin (ATTR) and light-chain (AL) amyloidosis. Recent advances in disease-modifying therapy have improved prognosis, however there is a critical need for real-world evidence to address knowledge gaps, particularly longer-term therapeutic outcomes and surveillance strategies. Methods: A multi-stakeholder process was undertaken to develop a consensus dataset for ATTR- and AL-amyloidosis. This process included surveys to rank the importance of potential data items, and a consensus meeting of the CRAR steering committee, (comprised of multidisciplinary clinical experts, and patient organization representatives). Patients and patient organizations supported the development and implementation of a patient-reported dataset. Results: Consensus data items include disease onset, progression, severity, treatments, and outcomes, as well as patient-reported outcomes. Both prospective and retrospective (including deceased) patient cohorts are included. Further baseline data will be presented on an initial cohort of patients. Conclusions: CRAR has been established to collect a longitudinal, multidisciplinary dataset that will evaluate amyloidosis care and outcomes. CRAR has launched at multiple specialty amyloidosis centers nationally and is continually expanding. The growth of this program will promote opportunities to assess real-world safety and efficacy and inform the cost-effectiveness of therapies while supporting patient recruitment for research.
Free-ranging pet cats (Felis catus) frequently kill wildlife but also return live prey to their owners. This raises welfare concerns if live animals released by cat owners subsequently die, since this is preventable, eg through prompt euthanasia. To estimate the mortality rate of birds released alive by cat owners, we examined the fates of 3,597 cat-attacked individuals submitted to four RSPCA wildlife centres in the UK. Individuals from 64 species were received but most cases (77%) involved just seven species commonly found in urban areas. The overall mortality rate (based on all individuals received at centres, ie including those which perished in transport, those which were euthanased on arrival and those which were admitted for care after having been triaged) was 78%; the post-admittance mortality rate (n = 2,070 birds admitted for care) was 62%. On average, individuals that perished (n = 2,798) survived for 3.0 days before dying or being euthanased. Juveniles were more likely to survive to release than adults, possibly because their small size means they are less likely to receive injuries that are ultimately fatal. Extrapolating from the limited data currently available, and applying conservative estimates at each stage, we estimate that a minimum of 0.3 million birds are released annually by cat owners but subsequently die. Substantial welfare improvements could be achieved if owners were more prepared to adopt strategies to limit hunting behaviour (eg fitting cats with collars and bells) and if owners and rehabilitators were able to effectively identify individuals with fatal injuries. The latter will require studies that quantify the effects of identifiable physical injuries on the likelihood of survival to release, in order to establish effective triage criteria.
Good judgment is often gauged against two gold standards – coherence and correspondence. Judgments are coherent if they demonstrate consistency with the axioms of probability theory or propositional logic. Judgments are correspondent if they agree with ground truth. When gold standards are unavailable, silver standards such as consistency and discrimination can be used to evaluate judgment quality. Individuals are consistent if they assign similar judgments to comparable stimuli, and they discriminate if they assign different judgments to dissimilar stimuli. We ask whether “superforecasters”, individuals with noteworthy correspondence skills (see Mellers et al., 2014) show superior performance on laboratory tasks assessing other standards of good judgment. Results showed that superforecasters either tied or out-performed less correspondent forecasters and undergraduates with no forecasting experience on tests of consistency, discrimination, and coherence. While multifaceted, good judgment may be a more unified than concept than previously thought.
Make-at-home nasal irrigation solutions are often recommended for treating chronic rhinosinusitis. Many patients will store pre-made solution for convenient use. This study investigated the microbiological properties of differing recipes and storage temperatures.
Method
Three irrigation recipes (containing sodium chloride, sodium bicarbonate and sucrose) were stored at 5oC and 22oC. Further samples were inoculated with Staphylococcus aureus and Pseudomonas aeruginosa. Sampling and culturing were conducted at intervals from day 0–12 to examine for bacterial presence or persistence.
Results
No significant bacterial growth was detected in any control solution stored at 5oC. Saline solutions remained relatively bacterial free, with poor survival of inoculated bacteria, which may be related to either lower pH or lower osmolality. Storing at room temperature increased the risk of contamination in control samples, particularly from pseudomonas.
Conclusion
If refrigerated, pre-made nasal irrigation solutions can be stored safely for up to 12 days without risking cross-contamination to irrigation equipment or patients.
Data from neurocognitive assessments may not be accurate in the context of factors impacting validity, such as disengagement, unmotivated responding, or intentional underperformance. Performance validity tests (PVTs) were developed to address these phenomena and assess underperformance on neurocognitive tests. However, PVTs can be burdensome, rely on cutoff scores that reduce information, do not examine potential variations in task engagement across a battery, and are typically not well-suited to acquisition of large cognitive datasets. Here we describe the development of novel performance validity measures that could address some of these limitations by leveraging psychometric concepts using data embedded within the Penn Computerized Neurocognitive Battery (PennCNB).
Methods:
We first developed these validity measures using simulations of invalid response patterns with parameters drawn from real data. Next, we examined their application in two large, independent samples: 1) children and adolescents from the Philadelphia Neurodevelopmental Cohort (n = 9498); and 2) adult servicemembers from the Marine Resiliency Study-II (n = 1444).
Results:
Our performance validity metrics detected patterns of invalid responding in simulated data, even at subtle levels. Furthermore, a combination of these metrics significantly predicted previously established validity rules for these tests in both developmental and adult datasets. Moreover, most clinical diagnostic groups did not show reduced validity estimates.
Conclusions:
These results provide proof-of-concept evidence for multivariate, data-driven performance validity metrics. These metrics offer a novel method for determining the performance validity for individual neurocognitive tests that is scalable, applicable across different tests, less burdensome, and dimensional. However, more research is needed into their application.