104 research outputs found
Using Verbal Autopsy to Measure Causes of Death: the Comparative Performance of Existing Methods.
Monitoring progress with disease and injury reduction in many populations will require widespread use of verbal autopsy (VA). Multiple methods have been developed for assigning cause of death from a VA but their application is restricted by uncertainty about their reliability. We investigated the validity of five automated VA methods for assigning cause of death: InterVA-4, Random Forest (RF), Simplified Symptom Pattern (SSP), Tariff method (Tariff), and King-Lu (KL), in addition to physician review of VA forms (PCVA), based on 12,535 cases from diverse populations for which the true cause of death had been reliably established. For adults, children, neonates and stillbirths, performance was assessed separately for individuals using sensitivity, specificity, Kappa, and chance-corrected concordance (CCC) and for populations using cause specific mortality fraction (CSMF) accuracy, with and without additional diagnostic information from prior contact with health services. A total of 500 train-test splits were used to ensure that results are robust to variation in the underlying cause of death distribution. Three automated diagnostic methods, Tariff, SSP, and RF, but not InterVA-4, performed better than physician review in all age groups, study sites, and for the majority of causes of death studied. For adults, CSMF accuracy ranged from 0.764 to 0.770, compared with 0.680 for PCVA and 0.625 for InterVA; CCC varied from 49.2% to 54.1%, compared with 42.2% for PCVA, and 23.8% for InterVA. For children, CSMF accuracy was 0.783 for Tariff, 0.678 for PCVA, and 0.520 for InterVA; CCC was 52.5% for Tariff, 44.5% for PCVA, and 30.3% for InterVA. For neonates, CSMF accuracy was 0.817 for Tariff, 0.719 for PCVA, and 0.629 for InterVA; CCC varied from 47.3% to 50.3% for the three automated methods, 29.3% for PCVA, and 19.4% for InterVA. The method with the highest sensitivity for a specific cause varied by cause. Physician review of verbal autopsy questionnaires is less accurate than automated methods in determining both individual and population causes of death. Overall, Tariff performs as well or better than other methods and should be widely applied in routine mortality surveillance systems with poor cause of death certification practices
A revised nitrogen budget for the Arabian Sea
Despite its importance for the global oceanic nitrogen (N) cycle, considerable uncertainties exist about the N fluxes of the Arabian Sea. On the basis of our recent measurements during the German Arabian Sea Process Study as part of the Joint Global Ocean Flux Study (JGOFS) in 1995 and 1997, we present estimates of various N sources and sinks such as atmospheric dry and wet depositions of N aerosols, pelagic denitrification, nitrous oxide (N2O) emissions, and advective N input from the south. Additionally, we estimated the N burial in the deep sea and the sedimentary shelf denitrification. On the basis of our measurements and literature data, the N budget for the Arabian Sea was reassessed. It is dominated by the N loss due to denitrification, which is balanced by the advective input of N from the south. The role of N fixation in the Arabian Sea is still difficult to assess owing to the small database available; however, there are hints that it might be more important than previously thought. Atmospheric N depositions are important on a regional scale during the intermonsoon in the central Arabian Sea; however, they play only a minor role for the overall N cycling. Emissions of N2O and ammonia, deep-sea N burial, and N inputs by rivers and marginal seas (i.e., Persian Gulf and Red Sea) are of minor importance. We found that the magnitude of the sedimentary denitrification at the shelf might be ∼17% of the total denitrification in the Arabian Sea, indicating that the shelf sediments might be of considerably greater importance for the N cycling in the Arabian Sea than previously thought. Sedimentary and pelagic denitrification together demand ∼6% of the estimated particulate organic nitrogen export flux from the photic zone. The main northward transport of N into the Arabian Sea occurs in the intermediate layers, indicating that the N cycle of the Arabian Sea might be sensitive to variations of the intermediate water circulation of the Indian Ocean
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Increased lymph node ratio predicts poor survival in pediatric rhabdomyosarcoma
Lymph Node Ratio (LNR) is defined as the number of positive lymph nodes (pLN) divided by total lymph nodes (LN) examined. LNR correlates with recurrence and/or overall survival in many adult cancers but has not previously been described in pediatric oncologic disease. We hypothesized that LNR correlates with worse disease specific survival (DSS) in pediatric rhabdomyosarcoma (RMS).
Patients <20 years who underwent surgery for RMS between 1988 and 2013 in the SEER database were analyzed.
188 patients with a mean age at diagnosis of 8.8 ± 6 years and a mean LNR of 0.13 ± 0.27 were identified. Univariate analysis found that alveolar type, positive lymph node (pLN), stage, site, LNR, and age had significantly worse survival. Cox regression analysis identified LNR > 0.75 (HR 4.32, P = 0.015), alveolar histology (HR 4.797, P 0.75 had a 22% 5 year and 0% 10 year survival (P <0.001).
LNR is superior to pLN status as an independent prognostic indicator of DSS in pediatric RMS.
Level III
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Disparities in pediatric gonadal torsion: Does gender, race and insurance status affect outcomes?
Ovarian and testicular torsions are emergencies requiring prompt surgical treatment to preserve gonadal function. However, diagnosis in females is often delayed owing to nonspecific symptoms. We sought to assess disparities in management and outcomes between males and females with torsion.
The National Inpatient Sample was queried for pediatric patients with "emergent", "urgent", or "trauma center" admission and ICD-9 codes for ovarian torsion and testicular torsion. Demographic data, operative procedure, gonadal loss, length of stay (LOS), total charges (TC), and mortality were recorded.
There were 2254 unweighted encounters. The average age was 11.56±5.30years for males and 12.55±3.72years for females (p<0.001). Among males, 90% underwent surgery (p<0.001), of which 40% required orchiectomy. Conversely, 73% of females had surgery (p<0.001), of which 78% had oophorectomy. Subsequent analysis with only patients who underwent surgery showed that insurance status (p=0.012), race (p<0.001), and U.S. region (p<0.001) were significantly different between males and females. Gender specific analyses showed that hospital control, hospital location/teaching status, and treatment year were also significant. As such, these six factors in addition to age and gender were used for propensity score matching (PSM). PSM produced two gender cohorts of 755 encounters each. Females had longer LOS (2.44±1.84days vs. 1.28±2.27days for males, p<0.001) and had higher TC (12,386.58±12,793.34), p<0.001. Logistic regression revealed that males (OR 0.163 [0.130-0.206]) and older patients (age OR 0.924 [0.903-0.946]) were less likely to undergo gonadal loss. Compared to those with private insurance, those with Medicare/Medicaid were more likely to have gonadal loss (1.401 [1.101-1.783]).
Disparities exist in the management of torsion based on gender. Overall, females had higher charges, had longer hospitalization, and were more likely to have gonadal loss despite current data supporting gonadal preservation for nearly all cases of ovarian torsion.
Level III Evidence
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Corrigendum to 'Disparities in Pediatric Gonadal Torsion: Does Gender, Race and Insurance Status Affect Outcomes?' [J Pediatr Surg 2018;53(7):1392-1395]
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Corrigendum to "Disparities in Pediatric Gonadal Torsion: Does Gender, Race and Insurance Status Affect Outcomes?" [J Pediatr Surgery. 2018 Jul;53(7):1392-1395]
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Waardenburg Syndrome Type IV De Novo SOX10 Variant Causing Chronic Intestinal Pseudo-Obstruction
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Treatment patterns and outcomes for pancreatic tumors in children: an analysis of the National Cancer Database
Pancreatic tumors are rare in children and limited data are available regarding incidence, treatment, and outcomes. We aim to describe patient and tumor characteristics and to report on survival of these diseases.
Children with pancreatic tumors were queried from the National Cancer Database (2004-2014). The association between treatment and hazard of death was assessed using Kaplan-Meier method and Cox regression model.
We identified 109 children with pancreatic tumors; 52% were male and median age at diagnosis was 14 years. Tumors were distributed as follows: pseudopapillary neoplasm (30%), endocrine tumors (27%), pancreatoblastoma (16%), pancreatic adenocarcinoma (16%), sarcoma (6%) and neuroblastoma (5%). Seventy-nine patients underwent surgery, of which 76% achieved R0 resection. Most patients (85%) had lymph nodes examined, of which 22% had positive nodes. Five-year overall survival by tumor histology was 95% (pseudopapillary neoplasm), 75% (neuroblastoma), 70% (pancreatoblastoma), 51% (endocrine tumors), 43% (sarcoma), and 34% (adenocarcinoma). On multivariable analysis, surgical resection was the strongest predictor of survival (HR 0.26, 95% CI 0.10-0.68, p < 0.01).
Overall survival of children with pancreatic tumors is grim, with varying survival rates among different tumors. Surgical resection is associated with improved long-term survival
The kinetic energy budget of monsoon circulation over the Indian region during ISMEX-1973
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