A CLINICAL DECISION-MAKING RULE FOR MILD HEAD INJURY IN CHILDREN LESS THAN THREE YEARS OLD

Public Health Significance: The objective of this study is to establish a clinical decision-making rule for mild head injury in young children, an extremely common type of injury seen in emergency departments. These children appear to respond differently to mild head injuries and face different developmental issues than do older children and management guidelines remain unclear.Methods: Subjects were 97 children less than three years old with mild head injury (ICD9 codes 800-804 and 850-854) and an initial Glasgow Coma Scale score of 14 or 15, consecutively evaluated at a Level 1 Pediatric Emergency Department. Demographic, injury, symptom and treatment characteristics were abstracted from the medical records. A classification and regression tree (CART) program was used to identify characteristics that were correlated with intracranial injury (ICI) among children in the study. The information garnered from the tree was used to construct a clinical decision-making rule for the evaluation of very young children with mild head injuries. A cost analysis was done to determine potential cost savings from the new decision-making rule.Results: Forty-six percent of the children were less than 12 months, 24% were 12-23 months and 30% were 24-35 months old at the time of injury. Three-quarters of all injuries occurred from falls. Almost 25% of the children had evidence of an ICI on the CT scan; more than two-thirds of the ICIs occurred in children less than 12 months old (p=0.03). We examined multiple CART models to assess the impact of different misclassification penalties and missing data. The main parent node on the final CART model was the presence of vision changes; splits also occurred with the presence of scalp lacerations, vomiting, the child being inconsolable, sex and area of residence. Minor changes in the way children without ICIs are treated could result in cost savings as much as $90,000 per year.Conclusion: While similarity exists between decision-making rules for older children and that found for this cohort, very young children have unique characteristics that merit further study and may require a separate decision-making process

Mechanisms Driving the Effect of Weight Loss on Arterial Stiffness

Aims Arterial stiffness decreases with weight loss in overweight and obese adults, but the mechanisms by which this occurs are poorly understood. We aimed to elucidate these mechanisms. Methods We evaluated carotid-femoral pulse wave velocity (cfPWV), a measure of aortic stiffness, and brachial-ankle pulse wave velocity (baPWV), a mixed measure of central and peripheral arterial stiffness, in 344 young adults (mean age 38 yrs, mean body mass index (BMI) 32.9 kg/m2, 23% male) at baseline, 6 and 12 months in a behavioral weight loss intervention. Linear mixed effects models were used to evaluate associations between weight loss and arterial stiffness and to examine the degree to which improvements in obesity-related factors explained these associations. Pattern-mixture models using indicator variables for dropout pattern and Markov Chain Monte Carlo multiple imputation were used to evaluate the influence of different missing data assumptions. Results At 6 months (7% mean weight loss from baseline), there was a statistically significant median decrease of 47.5 cm/s (interquartile range (IQR) -44.5, 148) in cfPWV (p<0.0001) and a mean decrease of 11.7 cm/s (standard deviation (SD) 91.4) in baPWV (p=0.049). At 12 months (6% mean weight loss from baseline) only cfPWV remained statistically significantly reduced from baseline (p=0.02). Change in BMI (p=0.01) was statistically significantly positively associated with change in cfPWV after adjustment for changes in mean arterial pressure (MAP) or any other measured obesity-related factor. Common carotid artery diameter (p=0.003) was associated and heart rate (p=0.08) and MAP (p=0.07) marginally associated longitudinally with cfPWV. Reductions in heart rate (p<0.0001) and C-reactive protein (p=0.02) were associated with reduced baPWV, and each removed the statistical significance of the effect of weight loss on baPWV. Pattern-mixture modeling revealed several differences between completers and non-completers in the models for cfPWV, but marginal parameter estimates changed little from the original models for either PWV measure. Conclusions The public health importance of this thesis is that firstly, weight loss improves arterial stiffness in overweight and obese young adults. Secondly, its effect on baPWV may be explained by concurrent reductions in heart rate and inflammation. Missing data did not appear to bias these results

How Well Do Raters Agree on the Development Stage of Caenorhabditis elegans?

The assessment of inter-rater reliability is a topic that is infrequently addressed in Caenorhabditis elegans research, despite the existence of sophisticated statistical methods and the strong interest in the field in obtaining reliable and accurate data. This study applies statistical modeling as a robust means of analyzing the performance of worm researchers measuring the stage of worm development in terms of the two independent factors that comprise "agreement", which are (1) accuracy, representing trueness, a lack of systematic differences, or lack of bias, and (2) precision, representing reliability or the extent to which random differences are small. In our study, multiple raters assessed the same sample of worms to determine the developmental stage of each animal, and we collected data linking each scorer with their assessment for each worm. To describe the agreement of the raters, we developed a structural equation model with latent variables and thresholds, which assumes that all the raters are jointly scoring each worm. This common factor model separately quantifies the two aspects of agreement. The stage-specific thresholds examine accuracy and characterize the relative biases of each rater during the scoring process. The factor loadings for each rater examine the precision and characterizes the random error of the rater. Within our group, we found that the overall agreement was good, while certain adjustments in particular raters would have decreased systematic differences. Hence, the use of developmental stage as an experimental outcome can be both accurate and precise

Non-random geographic distribution of patients with cutaneous T-cell lymphoma in the Greater Pittsburgh Area

Background: Environmental hazards may play a role in the etiology of cutaneous T-cell lymphoma (CTCL). Some studies have found an increased incidence of CTCL among workers in chemical science, transportation, and manufacturing industries, but other studies have not. This discrepancy may be attributable to population migration, complicating accurate assessment of lifetime exposures. The Pittsburgh population has very low migration rates and most CTCL patients seen at the University of Pittsburgh Medical Center (UPMC) Cutaneous Lymphoma Center are life-long local residents. The Greater Pittsburgh Area used to be an industrial hub. There are residential communities positioned within close proximity to inactive industrial sites that continue to contain pollutants.Objective: To determine whether CTCL patients’ residences cluster within specific Pittsburgh regions, in particular, those with high levels of environmental pollutants.Methods: Our study included patients diagnosed with CTCL at the UPMC Cutaneous Lymphoma Center between 2000 and 2012. We mapped the longitudinal and latitudinal coordinates of patients’ residences at diagnosis, superfund sites, toxic release inventory sites, particular matter levels, and dermatologists’ offices using ArcMap 10.1. We then performed a SaTScan analysis using zip codes to assess for geographic clustering of patients’ residences in the Pittsburgh metropolitan statistical area. We assessed for a correlation between case distribution and both environmental hazards sites and dermatologist density in the area.Results: We identified 274 patients with CTCL in the Greater Pittsburgh area. We identified a statistically significant geographic cluster (p&lt;.001) in zip code 15213, which is the most densely populated neighborhood in Pittsburgh and the site of the region’s only CTCL clinic.  We observed no relationship between the locations of superfund sites, toxic release inventory sites, or particular matter levels and CTCL case distribution.Conclusion: Our findings do not support an association between exposure to environmental toxins and CTCL. CTCL cases clustered in areas with the highest population density, which also happen to include a regional CTCL center. To evaluate a possibility of urban pollutants playing a role in etiology of CTCL, dermatologist density and access to care need to be addressed as potential confounders in the future studies

Non-random geographic distribution of patients with cutaneous T-cell lymphoma in the Greater Pittsburgh Area

Background: Environmental hazards may play a role in the etiology of cutaneous T-cell lymphoma (CTCL). Some studies have found an increased incidence of CTCL among workers in chemical science, transportation, and manufacturing industries, but other studies have not. This discrepancy may be attributable to population migration, complicating accurate assessment of lifetime exposures. The Pittsburgh population has very low migration rates and most CTCL patients seen at the University of Pittsburgh Medical Center (UPMC) Cutaneous Lymphoma Center are life-long local residents. The Greater Pittsburgh Area used to be an industrial hub. There are residential communities positioned within close proximity to inactive industrial sites that continue to contain pollutants.Objective: To determine whether CTCL patients’ residences cluster within specific Pittsburgh regions, in particular, those with high levels of environmental pollutants.Methods: Our study included patients diagnosed with CTCL at the UPMC Cutaneous Lymphoma Center between 2000 and 2012. We mapped the longitudinal and latitudinal coordinates of patients’ residences at diagnosis, superfund sites, toxic release inventory sites, particular matter levels, and dermatologists’ offices using ArcMap 10.1. We then performed a SaTScan analysis using zip codes to assess for geographic clustering of patients’ residences in the Pittsburgh metropolitan statistical area. We assessed for a correlation between case distribution and both environmental hazards sites and dermatologist density in the area.Results: We identified 274 patients with CTCL in the Greater Pittsburgh area. We identified a statistically significant geographic cluster (p&lt;.001) in zip code 15213, which is the most densely populated neighborhood in Pittsburgh and the site of the region’s only CTCL clinic.  We observed no relationship between the locations of superfund sites, toxic release inventory sites, or particular matter levels and CTCL case distribution.Conclusion: Our findings do not support an association between exposure to environmental toxins and CTCL. CTCL cases clustered in areas with the highest population density, which also happen to include a regional CTCL center. To evaluate a possibility of urban pollutants playing a role in etiology of CTCL, dermatologist density and access to care need to be addressed as potential confounders in the future studies

Impact of Coal Mining on Self-Rated Health among Appalachian Residents

Objective. To determine the impact of coal mining, measured as the number of coal mining-related facilities nearby one’s residence or employment in an occupation directly related to coal mining, on self-rated health in Appalachia. Methods. Unadjusted and adjusted ordinal logistic regression models calculated odds ratio estimates and associated 95% confidence intervals for the probability of having an excellent self-rated health response versus another response. Covariates considered in the analyses included number of coal mining-related facilities nearby one’s residence and employment in an occupation directly related to coal mining, as well as potential confounders age, sex, BMI, smoking status, income, and education. Results. The number of coal mining facilities near the respondent’s residence was not a statistically significant predictor of self-rated health. Employment in a coal-related occupation was a statistically significant predictor of self-rated health univariably; however, after adjusting for potential confounders, it was no longer a significant predictor. Conclusions. Self-rated health does not seem to be associated with residential proximity to coal mining facilities or employment in the coal industry. Future research should consider additional measures for the impact of coal mining

Correction: Patterns and Trends in Accidental Poisoning Deaths: Pennsylvania's Experience 1979-2014.

[This corrects the article DOI: 10.1371/journal.pone.0151655.]

Improvement in racial disparities in years of life lost in the USA since 1990

<div><p>Objective</p><p>To examine changes in cause-specific Years of Life Lost (YLL) by age, race, and sex group in the USA from 1990 to 2014.</p><p>Methods</p><p>60 million death reports from the National Center for Health Statistics (NCHS) were categorized by age group, sex, race, and cause of death. YLL were calculated using age-specific life expectancies. Age groups were: infants <1, children 1–19, adults 20–64, and older adults 65+.</p><p>Results</p><p>Blacks have historically experienced more years of life lost than whites or other racial groups in the USA. In the year 1990 the YLL per 100,000 population was 21,103 for blacks, 14,160 for whites, and 7,417 for others. Between 1990 and 2014 overall YLL in the USA improved by 10%, but with marked variations in the rate of change across age, race, and sex groups. Blacks (all ages, both sexes) showed substantial improvement with a 28% reduction in YLL, compared to whites (all ages, both sexes) who showed a 4% reduction. Among blacks, improvements were seen in all age groups: reductions of 43%, 48%, 28%, and 25% among infants, children, adults, and older adults, respectively. Among whites, reductions of 33%, 44%, and 18% were seen in infants, children, and older adults, but there was a 6% increase in YLL among white adults. YLL increased by 18% in white adult females and declined 1% in white adult males. American Indian/Alaska Native women also had worsening in YLL, with an 8% increase. Asian Pacific Islanders consistently had the lowest YLL across all ages. Whites had a higher proportion of YLL due to overdose; blacks had a higher proportion due to homicide at younger ages and to heart disease at older ages.</p><p>Conclusions</p><p>Race-based disparities in YLL in the USA since 1990 have narrowed considerably, largely as a result of improvements among blacks compared to whites. Adult white and American Indian / Alaskan Native females have experienced worsening YLL, while white males have experienced essentially no change. If recent trajectories continue, adult black/white disparities in YLL will continue to narrow.</p></div

YLL rates per 100,000 population, percent disparity, and percent change (in YLL per 100,000) from 1990 to 2014 by race, sex, and age group.

<p>YLL rates per 100,000 population, percent disparity, and percent change (in YLL per 100,000) from 1990 to 2014 by race, sex, and age group.</p

Comparison of the common factor model with rater behavior.

<p>Shown are bar-graphs depicting the percentages predicted for the assignment of animals to each stage by individual reviewers from the estimated common factor model (left column), and the observed percentage of animals assigned to each of the developmental stages for the raters (right column).</p