Measurement of Frontal Midline Theta Oscillations using OPM-MEG.

Optically pumped magnetometers (OPMs) are an emerging lightweight and compact sensor that can measure magnetic fields generated by the human brain. OPMs enable construction of wearable magnetoencephalography (MEG) systems, which offer advantages over conventional instrumentation. However, when trying to measure signals at low frequency, higher levels of inherent sensor noise, magnetic interference and movement artefact introduce a significant challenge. Accurate characterisation of low frequency brain signals is important for neuroscientific, clinical, and paediatric MEG applications and consequently, demonstrating the viability of OPMs in this area is critical. Here, we undertake measurement of theta band (4-8 Hz) neural oscillations and contrast a newly developed 174 channel triaxial wearable OPM-MEG system with conventional (cryogenic-MEG) instrumentation. Our results show that visual steady state responses at 4 Hz, 6 Hz and 8 Hz can be recorded using OPM-MEG with a signal-to-noise ratio (SNR) that is not significantly different to conventional MEG. Moreover, we measure frontal midline theta oscillations during a 2-back working memory task, again demonstrating comparable SNR for both systems. We show that individual differences in both the amplitude and spatial signature of induced frontal-midline theta responses are maintained across systems. Finally, we show that our OPM-MEG results could not have been achieved without a triaxial sensor array, or the use of postprocessing techniques. Our results demonstrate the viability of OPMs for characterising theta oscillations and add weight to the argument that OPMs can replace cryogenic sensors as the fundamental building block of MEG systems.

Enabling ambulatory movement in wearable magnetoencephalography with matrix coil active magnetic shielding.

The ability to collect high-quality neuroimaging data during ambulatory participant movement would enable a wealth of neuroscientific paradigms. Wearable magnetoencephalography (MEG) based on optically pumped magnetometers (OPMs) has the potential to allow participant movement during a scan. However, the strict zero magnetic field requirement of OPMs means that systems must be operated inside a magnetically shielded room (MSR) and also require active shielding using electromagnetic coils to cancel residual fields and field changes (due to external sources and sensor movements) that would otherwise prevent accurate neuronal source reconstructions. Existing active shielding systems only compensate fields over small, fixed regions and do not allow ambulatory movement. Here we describe the matrix coil, a new type of active shielding system for OPM-MEG which is formed from 48 square unit coils arranged on two planes which can compensate magnetic fields in regions that can be flexibly placed between the planes. Through the integration of optical tracking with OPM data acquisition, field changes induced by participant movement are cancelled with low latency (25 ms). High-quality MEG source data were collected despite the presence of large (65 cm translations and 270° rotations) ambulatory participant movements.

Naturalistic Hyperscanning with Wearable Magnetoencephalography.

The evolution of human cognitive function is reliant on complex social interactions which form the behavioural foundation of who we are. These social capacities are subject to dramatic change in disease and injury; yet their supporting neural substrates remain poorly understood. Hyperscanning employs functional neuroimaging to simultaneously assess brain activity in two individuals and offers the best means to understand the neural basis of social interaction. However, present technologies are limited, either by poor performance (low spatial/temporal precision) or an unnatural scanning environment (claustrophobic scanners, with interactions via video). Here, we describe hyperscanning using wearable magnetoencephalography (MEG) based on optically pumped magnetometers (OPMs). We demonstrate our approach by simultaneously measuring brain activity in two subjects undertaking two separate tasks-an interactive touching task and a ball game. Despite large and unpredictable subject motion, sensorimotor brain activity was delineated clearly, and the correlation of the envelope of neuronal oscillations between the two subjects was demonstrated. Our results show that unlike existing modalities, OPM-MEG combines high-fidelity data acquisition and a naturalistic setting and thus presents significant potential to investigate neural correlates of social interaction.

Triaxial detection of the neuromagnetic field using optically-pumped magnetometry: feasibility and application in children.

Optically-pumped magnetometers (OPMs) are an established alternative to superconducting sensors for magnetoencephalography (MEG), offering significant advantages including flexibility to accommodate any head size, uniform coverage, free movement during scanning, better data quality and lower cost. However, OPM sensor technology remains under development; there is flexibility regarding OPM design and it is not yet clear which variant will prove most effective for MEG. Most OPM-MEG implementations have either used single-axis (equivalent to conventional MEG) or dual-axis magnetic field measurements. Here we demonstrate use of a triaxial OPM formulation, able to characterise the full 3D neuromagnetic field vector. We show that this novel sensor is able to characterise magnetic fields with high accuracy and sensitivity that matches conventional (dual-axis) OPMs. We show practicality via measurement of biomagnetic fields from both the heart and the brain. Using simulations, we demonstrate how triaxial measurement offers improved cortical coverage, especially in infants. Finally, we introduce a new 3D-printed child-friendly OPM-helmet and demonstrate feasibility of triaxial measurement in a five-year-old. In sum, the data presented demonstrate that triaxial OPMs offer a significant improvement over dual-axis variants and are likely to become the sensor of choice for future MEG systems, particularly for deployment in paediatric populations.

Using OPM-MEG in contrasting magnetic environments.

Magnetoencephalography (MEG) has been revolutionised by optically pumped magnetometers (OPMs). "OPM-MEG" offers higher sensitivity, better spatial resolution, and lower cost than conventional instrumentation based on superconducting quantum interference devices (SQUIDs). Moreover, because OPMs are small, lightweight, and portable they offer the possibility of lifespan compliance and (with control of background field) motion robustness, dramatically expanding the range of MEG applications. However, OPM-MEG remains nascent technology; it places stringent requirements on magnetic shielding, and whilst a number of viable systems exist, most are custom made and there have been no cross-site investigations showing the reliability of data. In this paper, we undertake the first cross-site OPM-MEG comparison, using near identical commercial systems scanning the same participant. The two sites are deliberately contrasting, with different magnetic environments: a "green field" campus university site with an OPM-optimised shielded room (low interference) and a city centre hospital site with a "standard" (non-optimised) MSR (higher interference). We show that despite a 20-fold difference in background field, and a 30-fold difference in low frequency interference, using dynamic field control and software-based suppression of interference we can generate comparable noise floors at both sites. In human data recorded during a visuo-motor task and a face processing paradigm, we were able to generate similar data, with source localisation showing that brain regions could be pinpointed with just ∼10 mm spatial discrepancy and temporal correlations of > 80%. Overall, our study demonstrates that, with appropriate field control, OPM-MEG systems can be sited even in city centre hospital locations. The methods presented pave the way for wider deployment of OPM-MEG.

Longitudinal investigation of suicidal ideation and associated factors during pediatric acute lymphoblastic leukemia chemotherapy.

OBJECTIVE: This study describes the prevalence of suicidal ideation (SI) during acute lymphoblastic leukemia (ALL) therapy and investigates the influence of clinical factors and physical symptoms on SI. METHODS: The Children's Depressive Inventory (CDI-2) was administered to ALL patients (diagnosed 2012-2017) at start of consolidation, delayed intensification (DI), maintenance cycle 1 (MC1), and maintenance cycle 2 (MC2) in a multi-site study. SI was present if patients endorsed the item "I want to kill myself." Logistic regression models evaluated associations between SI and sociodemographic factors; depressive symptoms; and below average, average, and above average symptom clusters identified using latent class analysis of pain, nausea, fatigue, and sleep. RESULTS: Participants (n = 175) were 51% male, 75% high-/very high-risk disease, with a median age of 11.2 years at diagnosis (range: 7-18 years). Overall, 14.9% of patients (75% under age 12 years) endorsed SI during treatment, including 4% at start of consolidation, 9% at DI, 8% at MC1, and 4% at MC2. Non-Hispanic Other patients were 10.9-times (95% CI: 2.30-53.40) more likely than non-Hispanic Whites to endorse SI (p = 0.003). The frequency of SI was higher in patients experiencing above average (53.3%) compared to below average (4.1%, p = 0.003) symptoms. Depressive symptoms were consistently associated with SI. CONCLUSIONS: SI during the initial year of childhood ALL was more prevalent in children under the age of 12 years, from ethnic groups not typically associated with increased risk, and who endorsed increased physical and depressive symptoms. Findings highlight the need for improved screening of mental health problems to mitigate symptoms of distress.

An analysis of suicidal thoughts and behaviors among transgender and gender diverse adults.

PURPOSE: Suicidal thoughts and behaviors (STBs) remain a pressing public health problem for transgender and gender diverse (TGD) persons. The goal of this study was to apply social-ecological and minority stress frameworks to identify individual and interpersonal-level TGD-specific STB risk and protective factors. METHODS: This is a secondary analysis of the 2015 United States Transgender Health Survey, a comprehensive cross-sectional health assessment of a national sample of TGD adults (N = 27,658). Chi-square and Analysis of Variance (ANOVA) were used to identify bivariate correlates of 12-month and lifetime suicidal ideation (SI) and suicide attempt (SA). Logistic regression was employed to identify the strongest STB risk and protective factors across levels. RESULTS: Sexual minority identification, racial minority identification, and having a disability were lifetime STB risk factors. TGD identity, sexual minority identification, racial minority identification (SA only), lower education, lower income, military experience, having a disability, and being uninsured were 12-month STB risk factors. Psychological distress was the most robust STB risk factor. Workplace discrimination, family rejection, healthcare discrimination, and childhood bias-based victimization were lifetime STB risk factors. All forms of discrimination and victimization (with the exception of family rejection for SI) were 12-month STB risk factors. Family and coworker support were protective factors for lifetime SA (but not SI) and all 12-month STBs. Being less out about TGD identity was a protective factor for STBs (except for 12-month SI). CONCLUSION: Findings support social-ecological and minority stress STB risk frameworks. Recommendations are provided for a comprehensive approach to TGD suicide prevention.

Suicide Screening in a Large Pediatric Emergency Department: Results, Feasibility, and Lessons Learned.

OBJECTIVE: This study examined the feasibility of screening all patients entering the ED using the Columbia-Suicide Severity Rating Scale as well as examining the rates of suicide ideation and attempts endorsed by adolescents who present at the ED. METHODS: This study used a sample of 12,113 patients between the ages of 11 and 19 years. RESULTS: Results revealed that 13.5% of the participants endorsed passive suicide ideation in the month leading up to their ED visit and 11.3% of the participants reported active ideation in the prior month. Results also revealed that patients whose chief complaints were coded as psychiatric or medical trauma were more likely to endorse either active or passive suicidal ideation than other presenting problems. Patients with a psychiatric or medical trauma chief complaint were also more likely to report lifetime suicidal behavior and suicidal behavior 3 months before the ED visit. CONCLUSIONS: In addition to findings, implications, feasibility, and lessons learned are discussed for other institutions or departments considering implementation of a widespread screening.Highlights:• Suicide screenings were implemented in a large pediatric emergency department.• One in 5 endorsed suicidal ideation or behavior regardless of presenting problem.• Feasibility and lessons learned are discussed for others hoping to implement a widespread screening.

Caregiver behaviors and childhood maladaptive grief: Initial validation of the Grief Facilitation Inventory.

The Grief Facilitation Inventory (GFI) is a newly-developed measure of caregiver behaviors theorized to facilitate or hinder children's adaptive grief reactions. We examine its factor structure, reliability, and validity. An exploratory factor analysis identified four factors: Ongoing Connection, Existential Continuity/Support, Caregiver Grief Expression, and Grief Inhibition/Avoidance. Both child- and caregiver-report versions had adequate-to-good internal consistency. The child-report GFI showed evidence of criterion-referenced validity via significant correlations with measures of child maladaptive grief and other psychological symptoms. Results provide preliminary evidence of the reliability, validity, and clinical utility of the GFI as a measure of caregiver grief-facilitation behaviors.

The Impact of Bullying Victimization and Sexual Orientation on the Severity of Suicidal Behavior.

Background: Lesbian, gay, and bisexual youth face a disproportionate risk of suicidal ideation and attempt compared to heterosexual counterparts. Escalation from ideation to attempt can occur quickly, and youth who survive suicide attempts are likely to pursue subsequent, riskier attempts. This study examines the effects of bullying and sexual orientation on suicidal outcomes. Methods: Data came from the national, school-administered 2017 Youth Risk Behavior Survey (N = 14,765). Bivariate associations, binomial logistic regressions, and ordinal logistic regressions were performed. Results: Lesbian/gay, bisexual, and unsure youth reported greater odds of ideation and attempts compared to heterosexual youth. For ideation, increased effects were inconsistent across bullying types and significant interactions were found for bisexual youth who were bullied in school, and for lesbian/gay youth who were cyberbullied. Conclusion: These results underscore the need to understand bullying victimization for lesbian, gay, and bisexual youth. Awareness of increasing cyberbullying and creating school environments of no-bullying tolerance in the post-pandemic era are among the challenges ahead.

Measuring the cortical tracking of speech with optically-pumped magnetometers.

During continuous speech listening, brain activity tracks speech rhythmicity at frequencies matching with the repetition rate of phrases (0.2-1.5 Hz), words (2-4 Hz) and syllables (4-8 Hz). Here, we evaluated the applicability of wearable MEG based on optically-pumped magnetometers (OPMs) to measure such cortical tracking of speech (CTS). Measuring CTS with OPMs is a priori challenging given the complications associated with OPM measurements at frequencies below 4 Hz, due to increased intrinsic interference and head movement artifacts. Still, this represents an important development as OPM-MEG provides lifespan compliance and substantially improved spatial resolution compared with classical MEG. In this study, four healthy right-handed adults listened to continuous speech for 9 min. The radial component of the magnetic field was recorded simultaneously with 45-46 OPMs evenly covering the scalp surface and fixed to an additively manufactured helmet which fitted all 4 participants. We estimated CTS with reconstruction accuracy and coherence, and determined the number of dominant principal components (PCs) to remove from the data (as a preprocessing step) for optimal estimation. We also identified the dominant source of CTS using a minimum norm estimate. CTS estimated with reconstruction accuracy and coherence was significant in all 4 participants at phrasal and word rates, and in 3 participants (reconstruction accuracy) or 2 (coherence) at syllabic rate. Overall, close-to-optimal CTS estimation was obtained when the 3 (reconstruction accuracy) or 10 (coherence) first PCs were removed from the data. Importantly, values of reconstruction accuracy (~0.4 for 0.2-1.5-Hz CTS and ~0.1 for 2-8-Hz CTS) were remarkably close to those previously reported in classical MEG studies. Finally, source reconstruction localized the main sources of CTS to bilateral auditory cortices. In conclusion, t his study demonstrates that OPMs can be used for the purpose of CTS assessment. This finding opens new research avenues to unravel the neural network involved in CTS across the lifespan and potential alterations in, e.g., language developmental disorders. Data also suggest that OPMs are generally suitable for recording neural activity at frequencies below 4 Hz provided PCA is used as a preprocessing step; 0.2-1.5-Hz being the lowest frequency range successfully investigated here.

Theoretical advantages of a triaxial optically pumped magnetometer magnetoencephalography system.

The optically pumped magnetometer (OPM) is a viable means to detect magnetic fields generated by human brain activity. Compared to conventional detectors (superconducting quantum interference devices) OPMs are small, lightweight, flexible, and operate without cryogenics. This has led to a step change in instrumentation for magnetoencephalography (MEG), enabling a "wearable" scanner platform, adaptable to fit any head size, able to acquire data whilst subjects move, and offering improved data quality. Although many studies have shown the efficacy of 'OPM-MEG', one relatively untapped advantage relates to improved array design. Specifically, OPMs enable the simultaneous measurement of magnetic field components along multiple axes (distinct from a single radial orientation, as used in most conventional MEG systems). This enables characterisation of the magnetic field vector at all sensors, affording extra information which has the potential to improve source reconstruction. Here, we conduct a theoretical analysis of the critical parameters that should be optimised for effective source reconstruction. We show that these parameters can be optimised by judicious array design incorporating triaxial MEG measurements. Using simulations, we demonstrate how a triaxial array offers a dramatic improvement on our ability to differentiate real brain activity from sources of magnetic interference (external to the brain). Further, a triaxial system is shown to offer a marked improvement in the elimination of artefact caused by head movement. Theoretical results are supplemented by an experimental recording demonstrating improved interference reduction. These findings offer new insights into how future OPM-MEG arrays can be designed with improved performance.

Measuring functional connectivity with wearable MEG.

Optically-pumped magnetometers (OPMs) offer the potential for a step change in magnetoencephalography (MEG) enabling wearable systems that provide improved data quality, accommodate any subject group, allow data capture during movement and potentially reduce cost. However, OPM-MEG is a nascent technology and, to realise its potential, it must be shown to facilitate key neuroscientific measurements, such as the characterisation of brain networks. Networks, and the connectivities that underlie them, have become a core area of neuroscientific investigation, and their importance is underscored by many demonstrations of their disruption in brain disorders. Consequently, a demonstration of network measurements using OPM-MEG would be a significant step forward. Here, we aimed to show that a wearable 50-channel OPM-MEG system enables characterisation of the electrophysiological connectome. To this end, we measured connectivity in the resting state and during a visuo-motor task, using both OPM-MEG and a state-of-the-art 275-channel cryogenic MEG device. Our results show that resting-state connectome matrices from OPM and cryogenic systems exhibit a high degree of similarity, with correlation values >70%. In addition, in task data, similar differences in connectivity between individuals (scanned multiple times) were observed in cryogenic and OPM-MEG data, again demonstrating the fidelity of the OPM-MEG device. This is the first demonstration of network connectivity measured using OPM-MEG, and results add weight to the argument that OPMs will ultimately supersede cryogenic sensors for MEG measurement.

Precision magnetic field modelling and control for wearable magnetoencephalography.

Optically-pumped magnetometers (OPMs) are highly sensitive, compact magnetic field sensors, which offer a viable alternative to cryogenic sensors (superconducting quantum interference devices - SQUIDs) for magnetoencephalography (MEG). With the promise of a wearable system that offers lifespan compliance, enables movement during scanning, and provides higher quality data, OPMs could drive a step change in MEG instrumentation. However, this potential can only be realised if background magnetic fields are appropriately controlled, via a combination of optimised passive magnetic screening (i.e. enclosing the system in layers of high-permeability materials), and electromagnetic coils to further null the remnant magnetic field. In this work, we show that even in an OPM-optimised passive shield with extremely low (<2 nT) remnant magnetic field, head movement generates significant artefacts in MEG data that manifest as low-frequency interference. To counter this effect we introduce a magnetic field mapping technique, in which the participant moves their head to sample the background magnetic field using a wearable sensor array; resulting data are compared to a model to derive coefficients representing three uniform magnetic field components and five magnetic field gradient components inside the passive shield. We show that this technique accurately reconstructs the magnitude of known magnetic fields. Moreover, by feeding the obtained coefficients into a bi-planar electromagnetic coil system, we were able to reduce the uniform magnetic field experienced by the array from a magnitude of 1.3±0.3 nT to 0.29±0.07 nT. Most importantly, we show that this field compensation generates a five-fold reduction in motion artefact at 0‒2 Hz, in a visual steady-state evoked response experiment using 6 Hz stimulation. We suggest that this technique could be used in future OPM-MEG experiments to improve the quality of data, especially in paradigms seeking to measure low-frequency oscillations, or in experiments where head movement is encouraged.

Mouth magnetoencephalography: A unique perspective on the human hippocampus.

Traditional magnetoencephalographic (MEG) brain imaging scanners consist of a rigid sensor array surrounding the head; this means that they are maximally sensitive to superficial brain structures. New technology based on optical pumping means that we can now consider more flexible and creative sensor placement. Here we explored the magnetic fields generated by a model of the human hippocampus not only across scalp but also at the roof of the mouth. We found that simulated hippocampal sources gave rise to dipolar field patterns with one scalp surface field extremum at the temporal lobe and a corresponding maximum or minimum at the roof of the mouth. We then constructed a fitted dental mould to accommodate an Optically Pumped Magnetometer (OPM). We collected data using a previously validated hippocampal-dependant task to test the empirical utility of a mouth-based sensor, with an accompanying array of left and right temporal lobe OPMs. We found that the mouth sensor showed the greatest task-related theta power change. We found that this sensor had a mild effect on the reconstructed power in the hippocampus (~10% change) but that coherence images between the mouth sensor and reconstructed source images showed a global maximum in the right hippocampus. We conclude that augmenting a scalp-based MEG array with sensors in the mouth shows unique promise for both basic scientists and clinicians interested in interrogating the hippocampus.

Suicide Risk in Youth and Young Adults with Type 1 Diabetes: a Review of the Literature and Clinical Recommendations for Prevention.

PURPOSE OF REVIEW: The manuscript reviews the extant literature on suicide-related thoughts and behaviors among youth and young adults with pediatric diabetes. This evidence is presented within the context of current theories of the etiology of suicidal behavior to highlight how diabetes may contribute to suicide risk, and to support providers in understanding the interplay between pediatric diabetes and suicide risk. The manuscript also reviews evidence-based approaches to suicide prevention suitable for use in pediatric healthcare settings, with suggestions for their application to this unique population. RECENT FINDINGS: Several recent studies identify heightened rates of suicidal ideation, suicide attempts, and suicide among youth and young adults with pediatric diabetes, as compared with their peers without diabetes. Evidence-based suicide prevention approaches frequently emphasize the importance of reducing suicidal youths' access to potentially lethal means for suicidal behavior. This approach may require special considerations for youth with pediatric diabetes, due to their need to carry sufficient quantities of insulin and the dangers of inaccurate insulin dosing and/or overdose. Suggestions for suicide prevention for this population include risk screening as part of routine diabetes care, early prevention, education for youth and families, and provider awareness of risk factors, warning signs, and implications for diabetes care. Youth and young adults with diabetes reported elevated rates of suicide-related behaviors as compared with their peers without diabetes. Existing suicide prevention approaches may require substantial adaptation for use with youth and young adults with diabetes. Further research is needed to examine how to best prevent suicidal behaviors among this population.

Multi-channel whole-head OPM-MEG: Helmet design and a comparison with a conventional system.

Magnetoencephalography (MEG) is a powerful technique for functional neuroimaging, offering a non-invasive window on brain electrophysiology. MEG systems have traditionally been based on cryogenic sensors which detect the small extracranial magnetic fields generated by synchronised current in neuronal assemblies, however, such systems have fundamental limitations. In recent years, non-cryogenic quantum-enabled sensors, called optically-pumped magnetometers (OPMs), in combination with novel techniques for accurate background magnetic field control, have promised to lift those restrictions offering an adaptable, motion-robust MEG system, with improved data quality, at reduced cost. However, OPM-MEG remains a nascent technology, and whilst viable systems exist, most employ small numbers of sensors sited above targeted brain regions. Here, building on previous work, we construct a wearable OPM-MEG system with 'whole-head' coverage based upon commercially available OPMs, and test its capabilities to measure alpha, beta and gamma oscillations. We design two methods for OPM mounting; a flexible (EEG-like) cap and rigid (additively-manufactured) helmet. Whilst both designs allow for high quality data to be collected, we argue that the rigid helmet offers a more robust option with significant advantages for reconstruction of field data into 3D images of changes in neuronal current. Using repeat measurements in two participants, we show signal detection for our device to be highly robust. Moreover, via application of source-space modelling, we show that, despite having 5 times fewer sensors, our system exhibits comparable performance to an established cryogenic MEG device. While significant challenges still remain, these developments provide further evidence that OPM-MEG is likely to facilitate a step change for functional neuroimaging.

Measurement Invariance of the Persistent Complex Bereavement Disorder Checklist With Respect to Youth Gender, Race, Ethnicity, and Age.

The Persistent Complex Bereavement Disorder (PCBD) Checklist was constructed to facilitate the developmentally sensitive assessment of proposed PCBD criteria in bereaved children and adolescents 8-18 years of age. Initial analyses of the PCBD Checklist provided support for the hypothesized two-factor model. The purpose of the present study was to evaluate the measurement invariance of the PCBD Checklist with respect to gender (boys and girls), race/ethnicity (White, Black, and Hispanic youth), and age (school age, preadolescent, and adolescent youth). Participants were 594 youth (50.4% female) aged 7-18 years (M = 11.91, SD = 2.80) who were evaluated as part of standard care at a community-based grief support center. Youth self-identified as Hispanic (n = 184, 30.8%), non-Hispanic white (n = 179, 30.0%), and African American/Black (n = 136, 22.8%). A series of stepwise, multigroup confirmatory factor analyses provided evidence in support of the PCBD Checklist's measurement invariance for all three groups concerning configural invariance, metric invariance, and scalar invariance. These results suggest that PCBD Checklist Criterion B and C scores are measuring similar latent variables, to a similar degree, across gender, race/ethnicity, and age. Establishing the cross-group equivalence of the PCBD Checklist is an important endorsement of its generalizability and clinical utility in that it can be administered to diverse populations with confidence that it is measuring proposed PCBC diagnostic criteria similarly across subgroups.

Initial Validation and Measurement Invariance of the Active Inhibition Scale Among Traumatized and Grieving Youth.

The Active Inhibition Scale (AIS; Ayers, Sandler, & Twohey, 1998) is an 11-item, self-report measure of emotional suppression among children and adolescents. Previous research with the AIS has linked emotional suppression to several clinically significant outcomes, such as posttraumatic stress symptoms (PTSS) and suicide, among trauma-exposed and bereaved youth; however, there are no published evaluations of its psychometric properties. We examined the factor structure and criterion validity of the AIS in two samples. Sample 1 included youth (M = 12.22 years, SD = 2.96, range: 6-18 years; 55.4% female) referred to an outpatient psychology clinic specializing in childhood trauma and grief. Sample 2 included youth (M = 13.18 years, SD = 2.58, range: 8-18 years; 61.8% female) referred to a community grief counseling center. Confirmatory factor analytic results supported a one-factor solution, Cronbach's α = .94. Additionally, AIS scores correlated positively with PTSS, depression, and maladaptive grief, rs = .43-.64. Evidence of factorial invariance was found across gender, race/ethnicity, and age group. Emotional suppression scores were higher among girls compared to boys, Black and Hispanic youth compared to White youth, and older compared to younger age groups. The magnitude of correlations between AIS and symptom measure scores was comparable across groups. These results support the reliability and criterion validity of the AIS with diverse youth populations and underscore the role that emotional suppression may play in explaining group differences in mental health symptoms.

Calculating the incidence rate of sibling bereavement among children and adolescents across the United States: A proposed method.

This study proposes a method for calculating the annual incidence rate of sibling bereavement among US youth using national epidemiological data. The proposed model combines data on family household size with national death statistics to calculate the number of siblings affected by the death of a child annually. From 2012 to 2015, an average of 61,389 children per year experienced the death of a sibling, resulting in an estimate of 0.0832% of children bereaved by the death of a sibling annually. Data indicate a need for greater awareness and dialog concerning the frequency with which children experience the death of a sibling.