Prescription opioids, alcohol and fatal motor vehicle crashes: a population-based case-control study

Background The prevalence of prescription opioid use among drivers has increased markedly in the past two decades. The purpose of this study is to assess the associations of prescription opioid use and alcohol use with the risk of fatal crash involvement in US drivers. Methods We performed a population-based case-control study using toxicological testing data from two national data systems. Cases (n = 3606) were drivers involved in fatal motor vehicle crashes selected from the Fatality Analysis Reporting System and controls (n = 15,600) were drivers participating in the 2007 and 2013 National Roadside Surveys of Alcohol and Drug Use by Drivers. Multivariable logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs) of fatal crash involvement associated with prescription opioid use with and without the presence of alcohol. Results Overall, cases were significantly more likely than controls to test positive for prescription opioids (5.0% vs. 3.7%, p < 0.001), alcohol (56.2% vs. 7.1%, p < 0.0001), and both substances (2.2% vs. 0.2%, p < 0.001). Relative to drivers testing negative for prescription opioids and alcohol, the adjusted ORs of fatal crash involvement were 1.72 (95% CI: 1.37, 2.17) for those testing positive for prescription opioids and negative for alcohol, 17.92 (95% CI: 16.19, 19.84) for those testing positive for alcohol and negative for prescription opioids, and 21.89 (95% CI: 14.38, 33.32) for those testing positive for both substances. The interaction effect on fatal crash risk of prescription opioid use and alcohol use was not statistically significant on either additive or multiplicative scale. Conclusions Prescription opioid use is associated with a significantly increased risk of fatal crash involvement independently of alcohol use. Concurrent use of prescription opioids and alcohol is associated with a 21-fold increased risk of fatal crash involvement

A note on character square

We study the finite groups with an irreducible character χ satisfying the following hypothesis: χ2 has exactly two distinct irreducible constituents, and one of which is linear, and then obtain a result analogous to the Zhmud\u27s ([8])

Negative exponential behavior of image mutual information for pseudo-thermal light ghost imaging: Observation, modeling, and verification

When use the image mutual information to assess the quality of reconstructed image in pseudo-thermal light ghost imaging, a negative exponential behavior with respect to the measurement number is observed. Based on information theory and a few simple and verifiable assumptions, semi-quantitative model of image mutual information under varying measurement numbers is established. It is the Gaussian characteristics of the bucket detector output probability distribution that leads to this negative exponential behavior. Designed experiments verify the model.Comment: 13 pages, 6 figure

Binary sampling ghost imaging: add random noise to fight quantization caused image quality decline

When the sampling data of ghost imaging is recorded with less bits, i.e., experiencing quantization, decline of image quality is observed. The less bits used, the worse image one gets. Dithering, which adds suitable random noise to the raw data before quantization, is proved to be capable of compensating image quality decline effectively, even for the extreme binary sampling case. A brief explanation and parameter optimization of dithering are given.Comment: 8 pages, 7 figure

Emergency department visits for traumatic brain injury in a birth cohort of medicaid-insured children

Objectives: To analyse emergency department-based data on paediatric traumatic brain injury (TBI). Methods: This study constructed a retrospective cohort of 493 890 children who were born in New York City between 1999–2007 and who were enrolled in the New York Medicaid programme at the time of their birth and followed these children from birth to the end of 2007. Results: There were 62 089 injury-related emergency department visits, of which 1290 had ICD-9 codes consistent with TBI. Children with TBI were more likely to be male (59.4% vs 51.4%) and Hispanic (43.9% vs 26.3%) than those in the underlying birth cohort and were more than twice as likely to be admitted to the hospital for inpatient care (RR = 2.4, 95% CI = 2.2, 2.6). The most commonly listed cause of injury was falls (58.3%). Spatially-smoothed risk estimates indicated that some areas of the city are associated with a greater risk of paediatric TBI than others. Conclusions: Emergency department data can be used to describe paediatric TBI in ways not easily available through more routinely collected administrative health data. This information can be used to target prevention and control efforts