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Higher thalamic volume has been found in children with obsessive-compulsive disorder (OCD) and children with clinical-level symptoms within the general population (Boedhoe et al. 2017, Weeland et al. 2021a). Functionally distinct thalamic nuclei are an integral part of OCD-relevant brain circuitry.
We aimed to study the thalamic nuclei volume in relation to subclinical and clinical OCD across different age ranges. Understanding the role of thalamic nuclei and their associated circuits in pediatric OCD could lead towards treatment strategies specifically targeting these circuits.
We studied the relationship between thalamic nuclei and obsessive-compulsive symptoms (OCS) in a large sample of school-aged children from the Generation R Study (N = 2500) (Weeland et al. 2021b). Using the data from the ENIGMA-OCD working group we conducted mega-analyses to study thalamic subregional volume in OCD across the lifespan in 2,649 OCD patients and 2,774 healthy controls across 29 sites (Weeland et al. 2021c). Thalamic nuclei were grouped into five subregions: anterior, ventral, intralaminar/medial, lateral and pulvinar (Figure 1).
Both children with subclinical and clinical OCD compared with controls show increased volume across multiple thalamic subregions. Adult OCD patients have decreased volume across all subregions (Figure 2), which was mostly driven by medicated and adult-onset patients.
Our results suggests that OCD-related thalamic volume differences are global and not driven by particular subregions and that the direction of effects are driven by both age and medication status.
This study aimed to compare the effectiveness of pharmacological therapy with and without direct maxillary sinus saline irrigation for the management of chronic rhinosinusitis without polyps.
In this prospective randomised controlled trial, 39 non-operated patients were randomly assigned to be treated with direct maxillary sinus saline irrigation in conjunction with systemic antibiotics and topical sprays (n = 24) or with pharmacological therapy alone (n = 15). Endoscopy, Sino-Nasal Outcome Test and Lund–MacKay computed tomography scores were obtained before, six weeks after and one to two years after treatment.
Post-treatment Lund–Mackay computed tomography scores were significantly improved in both cohorts, with no inter-cohort difference identified. Post-treatment nasal endoscopy scores were significantly improved in the study group but were similar to those measured in the control group. The Sino-Nasal Outcome Test-20 results showed improvement in both cohorts, with no difference between treatment arms.
Maxillary sinus puncture and irrigation with saline, combined with pharmacological treatment improves endoscopic findings in patients with chronic rhinosinusitis without polyps, but has no beneficial effect on symptoms and imaging findings over conservative treatment alone.
The aim of the current study was to explore the effect of gender, age at onset, and duration on the long-term course of schizophrenia.
Twenty-nine centers from 25 countries representing all continents participated in the study that included 2358 patients aged 37.21 ± 11.87 years with a DSM-IV or DSM-5 diagnosis of schizophrenia; the Positive and Negative Syndrome Scale as well as relevant clinicodemographic data were gathered. Analysis of variance and analysis of covariance were used, and the methodology corrected for the presence of potentially confounding effects.
There was a 3-year later age at onset for females (P < .001) and lower rates of negative symptoms (P < .01) and higher depression/anxiety measures (P < .05) at some stages. The age at onset manifested a distribution with a single peak for both genders with a tendency of patients with younger onset having slower advancement through illness stages (P = .001). No significant effects were found concerning duration of illness.
Our results confirmed a later onset and a possibly more benign course and outcome in females. Age at onset manifested a single peak in both genders, and surprisingly, earlier onset was related to a slower progression of the illness. No effect of duration has been detected. These results are partially in accord with the literature, but they also differ as a consequence of the different starting point of our methodology (a novel staging model), which in our opinion precluded the impact of confounding effects. Future research should focus on the therapeutic policy and implications of these results in more representative samples.
Life course theorists posit that sensitive periods exist during life span development where risk and protective factors may be particularly predictive of psychological outcomes relative to other periods in life. While there have been between-cohort studies trying to examine differences in discrimination and depressive symptoms, these studies have not been designed to identify these sensitive periods, which are best modeled by examining intra-individual change across time. To identify sensitive periods where discrimination and shift-&-persist (S&P) – a coping strategy that may protect against the negative impact of discrimination – are most strongly predictive of depressive symptoms, we employed latent growth curve modeling using an accelerated longitudinal design to track intra-individual change in depressive symptoms from ages 20–69. Participants were 3,685 adults measured at three time points ~10 years apart from the Midlife in the United States study (Mage = 37.93, SD = 6.948 at Wave I). Results identified two sensitive periods in development where high levels of S&P interacted with discrimination to protect against depressive symptoms; during the 30s and a lagged effect where 40's S&P protected against depressive symptoms when participants were in their 50s. Implications for the life course study of discrimination, coping, and depression are discussed.
Expectant parents who live through perinatal loss experience intense grief, which is not always acknowledged or accepted. A screening tool to detect bereaved parents’ grief reactions can guide professionals, including perinatal palliative care teams, to provide follow-up for those in need. This review's goal is to identify and synthesize the international published literature on existent instruments specifically measuring the grieving process after any perinatal loss and to identify factors that could moderate grief reactions.
Systematic review (PROSPERO # CRD42018092555) with critical synthesis. PUBMED, Cochrane, and PsycINFO databases were searched in English language articles using the keywords “perinatal” AND (“grief” OR “bereavement” OR mourning) AND (“scale” OR “questionnaire” OR “measure” OR “assessment”) up to May 2018. Eligibility criteria included every study using a measure to assess perinatal grief after all kinds of perinatal losses, including validations and translations to other languages and interventions designed to alleviate grief symptoms.
A total of 67 papers met inclusion criteria. Seven instruments measuring perinatal grief published between 1984 and 2002 are described. The Perinatal Grief Scale (PGS) was used in 53 of the selected studies. Of those, 39 analyzed factors associated with grief reactions. Six articles used PGS scores to evaluate pre- and post-bereavement interventions. Studies in English language only might have limited the number of articles.
Significance of results
The PGS is the most used standardized measures to assess grief after perinatal loss. All parents living through any kind of perinatal loss should be screened.
This pooled analysis evaluated the predictors of clinical outcome in the short-term treatment of panic disorder.
Data were pooled from 4 randomized, placebo-controlled studies of venlafaxine XR in adult outpatients with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) panic disorder with or without agoraphobia (n=1595). Patients were randomly assigned to 10 to 12 weeks' treatment with either placebo or venlafaxine (fixed or flexible dosing, range from 75 mg/d to 225 mg/d). The primary efficacy measure was the proportion of patients free of full-symptom panic attacks at end point. Predictors included panic severity (<8 or ≥8 full-symptom panic attacks during each 2 week period in the 4 weeks prior to baseline) and gender. Other predictors included panic disorder, clinical global impressions, anxiety, somatic and psychic anxiety, depression, mood, phobias, fear, and avoidance.
In both the active treatment and placebo groups, males (65% and 50%, respectively) and those with low symptom severity (69% and 53%, respectively) were significantly (P<0.05) more likely to be panic-free at end point. For nearly all baseline ratings on clinical measures, greater symptom severity was associated with lower proportions of patients who were free from full-symptom panic attacks at end point. Change scores showing improvement in symptom severity following treatment were associated with higher proportions of patients who were free from full-symptom panic attacks at end point.
Panic-free status at end point was predicted by gender, panic disorder severity, and most baseline and change scores of clinical ratings scales.
The efficacy and tolerability of escitalopram in obsessive-compulsive disorder (OCD) were investigated in a 24-week, randomised, placebo-controlled, active-referenced, double blind study.
466 adults with OCD were randomised to escitalopram 10mg/day (N=116), escitalopram 20mg/day (N=116), paroxetine 40mg/day (N=119), or placebo (N=115) for 24 weeks. The pre-specified primary efficacy endpoint was the mean change in the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) total score from baseline to Week 12 based on the intent-to-treat population and last observation carried forward (LOCF) using analysis of variance (ANCOVA).
Escitalopram 20mg/day was superior to placebo on the primary endpoint. After 12 weeks, on the primary efficacy endpoint, there was a statistically significant difference from placebo for 20mg escitalopram and paroxetine. In the escitalopram 20mg/day group, the Y-BOCS total score was significantly lower than in the placebo group as early as Week 6. At Week 24, the proportion of remitters (Y-BOCS≤10, LOCF, pre-defined) was significantly greater (p<0.05) for 20mg escitalopram (41.2%) than placebo (27.4%), but not for 10mg escitalopram (36.6%) or paroxetine (37.9%). The response rate (≥25 decrease from baseline Y-BOCS, LOCF, pre-defined) was significantly greater than placebo (50.4%) for 20mg escitalopram (70.2%) and paroxetine (67.2%). Statistically significantly more patients withdrew from the placebo group (18%) due to lack of efficacy, than paroxetine (8%) or escitalopram 20mg/day groups (6%). More paroxetine-treated patients withdrew due to adverse events than escitalopram- or placebo-treated patients.
Escitalopram was efficacious and well tolerated in the treatment of OCD, with 20mg escitalopram showing statistically significant superiority at the primary efficacy endpoint.
To compare the efficacy of escitalopram 10 or 20 mg/day with placebo in preventing relapse during 24 weeks in outpatients with obsessive-compulsive disorder (OCD) who had responded to an initial 16-week open-label treatment with escitalopram.
A multinational, randomised, double blind, placebo-controlled, flexible to fixed dose relapse prevention study with escitalopram in outpatients with OCD. The study consisted of a 16-week open-label period with 10 to 20 mg escitalopram followed by a 24 week double blind, placebo-controlled period, and a 1 week taper period. Patients who had responded to treatment (≥25% decrease in the Yale-Brown Obsessive Compulsive Scale (Y-BOCS) total score) by the end of the 16-week open-label period were eligible for randomisation to either escitalopram or placebo for a further 24 weeks.
468 patients with OCD were treated with open-label escitalopram (10 mg or 20 mg) for 16 weeks. There were 320 responders (68%) who were randomised to change to placebo (n=157) or to continue with escitalopram (at the assigned dose) for further 24 weeks (n=163). The primary analysis (time to relapse) showed a clear beneficial effect of escitalopram relative to placebo (log-rank test, p<0.001). The proportion of patients who relapsed was statistically significantly higher in the placebo group (52%) than in the escitalopram group (23%) (p<0.001, chi-square test). The risk of relapse was 2.74 times higher for placebo- than for escitalopram-treated patients (chi-square test, p<0.001). Escitalopram was well tolerated.
Escitalopram was effective in preventing relapse of OCD and was well tolerated as continuation treatment.
Two common approaches to identify subgroups of patients with bipolar disorder are clustering methodology (mixture analysis) based on the age of onset, and a birth cohort analysis. This study investigates if a birth cohort effect will influence the results of clustering on the age of onset, using a large, international database.
The database includes 4037 patients with a diagnosis of bipolar I disorder, previously collected at 36 collection sites in 23 countries. Generalized estimating equations (GEE) were used to adjust the data for country median age, and in some models, birth cohort. Model-based clustering (mixture analysis) was then performed on the age of onset data using the residuals. Clinical variables in subgroups were compared.
There was a strong birth cohort effect. Without adjusting for the birth cohort, three subgroups were found by clustering. After adjusting for the birth cohort or when considering only those born after 1959, two subgroups were found. With results of either two or three subgroups, the youngest subgroup was more likely to have a family history of mood disorders and a first episode with depressed polarity. However, without adjusting for birth cohort (three subgroups), family history and polarity of the first episode could not be distinguished between the middle and oldest subgroups.
These results using international data confirm prior findings using single country data, that there are subgroups of bipolar I disorder based on the age of onset, and that there is a birth cohort effect. Including the birth cohort adjustment altered the number and characteristics of subgroups detected when clustering by age of onset. Further investigation is needed to determine if combining both approaches will identify subgroups that are more useful for research.
The aim of the current study was to explore the changing interrelationships among clinical variables through the stages of schizophrenia in order to assemble a comprehensive and meaningful disease model.
Twenty-nine centers from 25 countries participated and included 2358 patients aged 37.21 ± 11.87 years with schizophrenia. Multiple linear regression analysis and visual inspection of plots were performed.
The results suggest that with progression stages, there are changing correlations among Positive and Negative Syndrome Scale factors at each stage and each factor correlates with all the others in that particular stage, in which this factor is dominant. This internal structure further supports the validity of an already proposed four stages model, with positive symptoms dominating the first stage, excitement/hostility the second, depression the third, and neurocognitive decline the last stage.
The current study investigated the mental organization and functioning in patients with schizophrenia in relation to different stages of illness progression. It revealed two distinct “cores” of schizophrenia, the “Positive” and the “Negative,” while neurocognitive decline escalates during the later stages. Future research should focus on the therapeutic implications of such a model. Stopping the progress of the illness could demand to stop the succession of stages. This could be achieved not only by both halting the triggering effect of positive and negative symptoms, but also by stopping the sensitization effect on the neural pathways responsible for the development of hostility, excitement, anxiety, and depression as well as the deleterious effect on neural networks responsible for neurocognition.
Obsessive-compulsive disorder (OCD) is a highly disabling condition, with frequent early onset. Adult/adolescent OCD has been extensively investigated, but little is known about prevalence and clinical characterization of geriatric patients with OCD (G-OCD = 65 years). The present study aimed to assess prevalence of G-OCD and associated socio-demographic and clinical correlates in a large international sample.
Data from 416 outpatients, participating in the ICOCS network, were assessed and categorized into 2 groups, age < vs = 65 years, and then divided on the basis of the median age of the sample (age < vs = 42 years). Socio-demographic and clinical variables were compared between groups (Pearson Chi-squared and t tests).
G-OCD compared with younger patients represented a significant minority of the sample (6% vs 94%, P < .001), showing a significantly later age at onset (29.4 ± 15.1 vs 18.7 ± 9.2 years, P < .001), a more frequent adult onset (75% vs 41.1%, P < .001) and a less frequent use of cognitive-behavioural therapy (CBT) (20.8% vs 41.8%, P < .05). Female gender was more represented in G-OCD patients, though not at a statistically significant level (75% vs 56.4%, P = .07). When the whole sample was divided on the basis of the median age, previous results were confirmed for older patients, including a significantly higher presence of women (52.1% vs 63.1%, P < .05).
G-OCD compared with younger patients represented a small minority of the sample and showed later age at onset, more frequent adult onset and lower CBT use. Age at onset may influence course and overall management of OCD, with additional investigation needed.
Intermittent explosive disorder (IED) is characterised by impulsive anger attacks that vary greatly across individuals in severity and consequence. Understanding IED subtypes has been limited by lack of large, general population datasets including assessment of IED. Using the 17-country World Mental Health surveys dataset, this study examined whether behavioural subtypes of IED are associated with differing patterns of comorbidity, suicidality and functional impairment.
IED was assessed using the Composite International Diagnostic Interview in the World Mental Health surveys (n = 45 266). Five behavioural subtypes were created based on type of anger attack. Logistic regression assessed association of these subtypes with lifetime comorbidity, lifetime suicidality and 12-month functional impairment.
The lifetime prevalence of IED in all countries was 0.8% (s.e.: 0.0). The two subtypes involving anger attacks that harmed people (‘hurt people only’ and ‘destroy property and hurt people’), collectively comprising 73% of those with IED, were characterised by high rates of externalising comorbid disorders. The remaining three subtypes involving anger attacks that destroyed property only, destroyed property and threatened people, and threatened people only, were characterised by higher rates of internalising than externalising comorbid disorders. Suicidal behaviour did not vary across the five behavioural subtypes but was higher among those with (v. those without) comorbid disorders, and among those who perpetrated more violent assaults.
The most common IED behavioural subtypes in these general population samples are associated with high rates of externalising disorders. This contrasts with the findings from clinical studies of IED, which observe a preponderance of internalising disorder comorbidity. This disparity in findings across population and clinical studies, together with the marked heterogeneity that characterises the diagnostic entity of IED, suggests that it is a disorder that requires much greater research.
Epidemiological studies indicate that individuals with one type of mental disorder have an increased risk of subsequently developing other types of mental disorders. This study aimed to undertake a comprehensive analysis of pair-wise lifetime comorbidity across a range of common mental disorders based on a diverse range of population-based surveys.
The WHO World Mental Health (WMH) surveys assessed 145 990 adult respondents from 27 countries. Based on retrospectively-reported age-of-onset for 24 DSM-IV mental disorders, associations were examined between all 548 logically possible temporally-ordered disorder pairs. Overall and time-dependent hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using Cox proportional hazards models. Absolute risks were estimated using the product-limit method. Estimates were generated separately for men and women.
Each prior lifetime mental disorder was associated with an increased risk of subsequent first onset of each other disorder. The median HR was 12.1 (mean = 14.4; range 5.2–110.8, interquartile range = 6.0–19.4). The HRs were most prominent between closely-related mental disorder types and in the first 1–2 years after the onset of the prior disorder. Although HRs declined with time since prior disorder, significantly elevated risk of subsequent comorbidity persisted for at least 15 years. Appreciable absolute risks of secondary disorders were found over time for many pairs.
Survey data from a range of sites confirms that comorbidity between mental disorders is common. Understanding the risks of temporally secondary disorders may help design practical programs for primary prevention of secondary disorders.
Childhood maltreatment (CM) plays an important role in the development of major depressive disorder (MDD). The aim of this study was to examine whether CM severity and type are associated with MDD-related brain alterations, and how they interact with sex and age.
Within the ENIGMA-MDD network, severity and subtypes of CM using the Childhood Trauma Questionnaire were assessed and structural magnetic resonance imaging data from patients with MDD and healthy controls were analyzed in a mega-analysis comprising a total of 3872 participants aged between 13 and 89 years. Cortical thickness and surface area were extracted at each site using FreeSurfer.
CM severity was associated with reduced cortical thickness in the banks of the superior temporal sulcus and supramarginal gyrus as well as with reduced surface area of the middle temporal lobe. Participants reporting both childhood neglect and abuse had a lower cortical thickness in the inferior parietal lobe, middle temporal lobe, and precuneus compared to participants not exposed to CM. In males only, regardless of diagnosis, CM severity was associated with higher cortical thickness of the rostral anterior cingulate cortex. Finally, a significant interaction between CM and age in predicting thickness was seen across several prefrontal, temporal, and temporo-parietal regions.
Severity and type of CM may impact cortical thickness and surface area. Importantly, CM may influence age-dependent brain maturation, particularly in regions related to the default mode network, perception, and theory of mind.
Evidence suggests that skin picking disorder (SPD) could be a prevalent condition associated with comorbidity and psychosocial dysfunction. However, just a few studies have assessed the prevalence and correlates of SPD in samples from low- and middle-income countries. In addition, the impact of SPD on quality of life (QoL) dimension after multivariable adjustment to potential confounders remains unclear.
Data were obtained from a Brazilian anonymous Web-based research platform. Participants provided sociodemographic data and completed the modified Skin Picking–Stanford questionnaire, the Hypomania Checklist (HCL-32), the Patient Health Questionnaire-9 (PHQ-9), the Fagerström Test for Nicotine Dependence, Alcohol Use Disorder Identification Test (AUDIT), Symptom Checklist-90-Revised inventory (SCL-90R), early trauma inventory self report–short form, and the World Health Organization quality of life abbreviated scale (WHOQOL-Bref). Associations were adjusted to potential confounders through multivariable models.
For our survey, 7639 participants took part (71.3% females; age: 27.2±7.9 years). The prevalence of SPD was 3.4% (95% CI: 3.0–3.8%), with a female preponderance (P<0.001). In addition, SPD was associated with a positive screen for a major depressive episode, nicotine dependence, and alcohol dependence, as well as suicidal ideation. Physical and psychological QoL was significantly more impaired in participants with SPD compared to those without SPD, even after adjustment for comorbidity.
In this large sample, SPD was a prevalent condition associated with co-occurring depression, nicotine, and alcohol dependence. In addition, SPD was independently associated with impaired physical and psychological QoL. Public health efforts toward the early recognition and treatment of SPD are warranted.
Research on post-traumatic stress disorder (PTSD) course finds a substantial proportion of cases remit within 6 months, a majority within 2 years, and a substantial minority persists for many years. Results are inconsistent about pre-trauma predictors.
The WHO World Mental Health surveys assessed lifetime DSM-IV PTSD presence-course after one randomly-selected trauma, allowing retrospective estimates of PTSD duration. Prior traumas, childhood adversities (CAs), and other lifetime DSM-IV mental disorders were examined as predictors using discrete-time person-month survival analysis among the 1575 respondents with lifetime PTSD.
20%, 27%, and 50% of cases recovered within 3, 6, and 24 months and 77% within 10 years (the longest duration allowing stable estimates). Time-related recall bias was found largely for recoveries after 24 months. Recovery was weakly related to most trauma types other than very low [odds-ratio (OR) 0.2–0.3] early-recovery (within 24 months) associated with purposefully injuring/torturing/killing and witnessing atrocities and very low later-recovery (25+ months) associated with being kidnapped. The significant ORs for prior traumas, CAs, and mental disorders were generally inconsistent between early- and later-recovery models. Cross-validated versions of final models nonetheless discriminated significantly between the 50% of respondents with highest and lowest predicted probabilities of both early-recovery (66–55% v. 43%) and later-recovery (75–68% v. 39%).
We found PTSD recovery trajectories similar to those in previous studies. The weak associations of pre-trauma factors with recovery, also consistent with previous studies, presumably are due to stronger influences of post-trauma factors.
Sexual assault is a global concern with post-traumatic stress disorder (PTSD), one of the common sequelae. Early intervention can help prevent PTSD, making identification of those at high risk for the disorder a priority. Lack of representative sampling of both sexual assault survivors and sexual assaults in prior studies might have reduced the ability to develop accurate prediction models for early identification of high-risk sexual assault survivors.
Data come from 12 face-to-face, cross-sectional surveys of community-dwelling adults conducted in 11 countries. Analysis was based on the data from the 411 women from these surveys for whom sexual assault was the randomly selected lifetime traumatic event (TE). Seven classes of predictors were assessed: socio-demographics, characteristics of the assault, the respondent's retrospective perception that she could have prevented the assault, other prior lifetime TEs, exposure to childhood family adversities and prior mental disorders.
Prevalence of Diagnostic and Statistical Manual of Mental Disorders IV (DSM-IV) PTSD associated with randomly selected sexual assaults was 20.2%. PTSD was more common for repeated than single-occurrence victimization and positively associated with prior TEs and childhood adversities. Respondent's perception that she could have prevented the assault interacted with history of mental disorder such that it reduced odds of PTSD, but only among women without prior disorders (odds ratio 0.2, 95% confidence interval 0.1–0.9). The final model estimated that 40.3% of women with PTSD would be found among the 10% with the highest predicted risk.
Whether counterfactual preventability cognitions are adaptive may depend on mental health history. Predictive modelling may be useful in targeting high-risk women for preventive interventions.
Background: The surgical risk factors and neuro-imaging characteristics associated with cerebellar mutism (CM) remain unclear and require further investigation. We aimed to examine surgical and MRI findings associated with CM in children following posterior fossa tumor resection. Methods: Using our data registry, we retrospectively collected data from pediatric patients who acquired CM and were matched based on age and pathology type with patients not acquiring CM after posterior fossa surgery. The strength of association between surgical and MRI variables and CM were examined using odds ratios (ORs) and corresponding 95% confidence intervals (CIs). Results: A total of 22 patients were included. Medulloblastoma was the most common pathology among CM patients (91%). Tumor attachment to the floor of the fourth ventricle (OR, 6; 95% CI, 0.7-276), calcification/hemosiderin deposition (OR 7; 95% CI 0.9-315.5), and post-operative peri-ventricular ischemia on MRI (OR, 5; 95% CI, 0.5-236.5) were found to have the highest association with CM. Conclusions: Our results may suggest that tumor attachment to the floor of the fourth ventricle, pathological calcification, and post-operative ischemia are relatively more prevalent in patients with CM. Collectively, our work calls for a larger multi-institutional study of CM patients to further investigate the determinants and management of CM to potentially minimize its development and predict onset.
Introduction: The Canadian Triage and Acuity Scale (CTAS) is the standard used in all Canadian (and many international) emergency departments (EDs) for establishing the priority by which patients should be assessed. In addition to its clinical utility, CTAS has become an important administrative metric used by governments to estimate patient care requirements, ED funding and workload models. Despite its importance, the process by which CTAS scores are derived is highly variable. Emphasis on ED wait times has also drawn attention to the length of time the triage process takes. The primary objective of this study was to determine the interrater agreement of CTAS in current clinical practice. The secondary objective was to determine the time it takes to triage in a variety of ED settings. Methods: This was a prospective, observational study conducted in 7 hospital EDs, selected to represent a mix of triage processes (electronic vs. manual), documentation practices (electronic vs. paper), hospital types (rural, community and teaching) and patient volumes (annual ED census ranged from 38,000 to 136,000). An expert CTAS auditor observed on-duty triage nurses in the ED and assigned independent CTAS in real time. Research assistants not involved in the triage process independently recorded the triage time. Interrater agreement was estimated using unweighted and quadratic-weighted kappa statistics with 95% confidence intervals (CIs). Results: 738 consecutive patient CTAS assessments were audited over 21 seven-hour triage shifts. Exact modal agreement was achieved for 554 (75.0%) patients. Using the auditor’s CTAS score as the reference standard, on-duty triage nurses over-triaged 89 (12.1%) and under-triaged 95 (12.9%) patients. Interrater agreement was “good” with an unweighted kappa of 0.63 (95% CI: 0.58, 0.67) and quadratic-weighted kappa of 0.79 (95% CI: 0.67, 0.90). Research assistants captured triage time for 3808 patients over 69 shifts at 7 different EDs. Median (IQR) triage time was 5.2 (3.8, 7.3) minutes and ranged from 3.9 (3.1, 4.8) minutes to 7.5 (5.8, 10.8) minutes. Conclusion: Variability in the accuracy, and length of time taken to perform CTAS assessments suggest that a standardized approach to performing CTAS assessments would improve both clinical decision making, and administrative data accuracy.