Crash momentum index and closing velocity as crash severity index

The velocity change Δ V of a vehicle subject to a collision, widely recognized as an efficient crash severity indicator, is a typical ‘a posteriori’ parameter, not generally known until the crash phase has been reconstructed. Δ V is the result of a combination of factors, regarding the impact velocities of the colliding vehicles and the geometry of the impact (as eccentricity, etc.): for this reason, its value alone gives no clear indications on the actions which can be undertaken to reduce crash severity. This feature is particularly critical in some application fields, for example, in case of advanced driver assistance systems assessment in different accident scenarios. This work proposes the disaggregation of Δ V into two different ‘a priori’ parameters to assess crash severity of an impact before its occurrence: the crash momentum index, representing the impact configuration, and the closing velocity projected along the principal direction of force ( Vr_pdof), as an index of the kinetic energy exchanged between the two vehicles. It is preliminarily shown how the proposed parameters can be calculated using established procedures – as momentum-based analysis – in a predictive (‘a priori’) approach. It is also evidenced how crash momentum index, Vr_pdof and the velocity change Δ V are in relation. To illustrate the procedure by means of examples, binary logistic regression on accident data is applied to correlate crash momentum index and Δ V to injury risk at Maximum Abbreviated Injury Scale level higher than 2. The use of crash momentum index as an additional severity index allows an improved correlation with injury risk, for the dataset used, in case of front and near side impacts. The use of the plane Vr_pdof– crash momentum index, on which curves at constant injury risk are drawn, provides clear indications on the possible strategies to reduce injury risk, as shown by generic examples to which the predictive procedure is applied.

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The Impact of Sidewalks on Vehicle-Pedestrian Crash Severity

International Journal of Statistics and Probability ◽

10.5539/ijsp.v7n4p69 ◽

2018 ◽

Vol 7 (4) ◽

pp. 69

Author(s):

Mehrnaz Doustmohammadi ◽

Niloufar Shirani Bidabadi ◽

Sumalatha Kesaveraddy ◽

Michael Anderson

Keyword(s):

Logistic Regression ◽

Statistical Analysis ◽

Traffic Congestion ◽

Binary Logistic Regression ◽

Crash Severity ◽

Mode Of Transportation ◽

The Difference ◽

Pedestrian Crashes ◽

The Impact

Walking is a sustainable mode of transportation that has several benefits related to improved health and reducing traffic congestion. The drawback to walking as a mode of transportation is the increased potential to be involved in a severe crash, which is greater than when two automobiles are involved in a crash. This paper provides a statistical analysis of pedestrian crashes that occurred in two Alabama cities where the crashes are divided into those where a sidewalk was present and those where a sidewalk was not present. The goal of the paper is to determine the difference in crash experiences and variables that contribute to vehicle-pedestrian crashes associated with the presence of the sidewalk. The paper uses binary logistic regression to develop models of pedestrian crashes and evaluates the models to determine factors that contribute the pedestrian crashes. The paper concludes that pedestrian crashes often happen in the evenings, with low lighting and visibility levels, independent of the presence of sidewalks.

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The Impact of ANxA6 Gene Polymorphism on the Efficacy of Methotrexate Treatment in Psoriasis Patients

Dermatology ◽

10.1159/000514072 ◽

2021 ◽

pp. 1-9

Author(s):

Zhijia Fan ◽

Zhenghua Zhang ◽

Qiong Huang ◽

Ling Han ◽

Xu Fang ◽

...

Keyword(s):

Clinical Efficacy ◽

Binary Logistic Regression ◽

Severity Index ◽

Term Treatment ◽

Nucleotide Polymorphisms ◽

Short Term ◽

Interindividual Variations ◽

Long Term Treatment ◽

Pasi Score ◽

The Impact

Background: There are great interindividual variations in the clinical efficacy of methotrexate (MTX) treatment and patients’ genetic background seems promising in its explanation. Objectives: The study aimed to test whether the polymorphism of annexin A6 (ANxA6) gene, a susceptibility factor for psoriasis, was associated with the clinical response to MTX therapy. Methods: A total of 325 patients enrolled in the study received oral MTX treatment, of whom 310 completed the 1-year study and performed the genotype analysis. They were defined as responders (a reduction of Psoriasis Area and Severity Index [PASI] score ≥75%) and nonresponders (a reduction of PASI <50%) compared to baseline after 12 weeks of short-time therapy. On 1-year treatment, they were defined as responders if they achieved PASI75 and absolute PASI ≤3, otherwise as nonresponders. The genotypes of 4 single-nucleotide polymorphisms (SNPs) in the ANxA6 gene were verified using the Sequenom platform. Potential predictors associated with the treatment outcome of MTX were assessed by binary logistic regression. Results: We found significant associations for the ANxA6 SNPs of rs11960458, rs960709, and rs13168551 with psoriasis severity. Patients with rs11960458 CC genotype and rs960709 GG genotype showed higher percentages of PASI75 and improvement rates of PASI at 12 weeks. And on 1-year treatment, statistical difference occurred in rs11960458 rather than other SNPs compared between responders and nonresponders that the frequency of CC genotype was higher in responders (p = 0.019). After adjustment for potential confounders, patients with rs11960458 TT/CT genotype (at 12 weeks: OR 0.483, 95% CI 0.245–0.951, p = 0.035; at 1 year: OR 0.483, 95% CI 0.280–0.833, p = 0.009) were significantly more likely to not respond to MTX both on the short-term and long-term treatment, while rs960709 and rs13168551 polymorphisms were only associated with the short-term efficacy of MTX (p = 0.018 and p = 0.036, respectively). Conclusions: The CC genotype of ANxA6 (rs11960458) was significantly associated with a better response when compared to those patients with the TT/CT genotype, thus being a potential predictor for the clinical efficacy of MTX.

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Cycling injuries in London: the impact of motor vehicle and cycle volumes, and road characteristics including speed limits

10.31235/osf.io/q5kz2 ◽

2018 ◽

Author(s):

Rachel Aldred ◽

Anna Goodman ◽

John Gulliver ◽

James Woodcock

Keyword(s):

Injury Risk ◽

Motor Vehicle ◽

Binary Logistic Regression ◽

Flow Data ◽

Binary Logistic Regression Model ◽

Speed Limits ◽

Route Network ◽

Logarithmic Unit ◽

Safety In Numbers ◽

The Impact

Cycling injury risk is an important topic, but few studies explore cycling risk in relation to exposure. This is largely because of a lack of exposure data, in other words how much cycling is done at different locations. This paper helps to fill this gap. It reports a case-control study of cycling injuries in London in 2013-2014, using modelled cyclist flow data alongside datasets covering some characteristics of the London route network. A multilevel binary logistic regression model is used to investigate factors associated with injury risk, comparing injury sites with control sites selected using the modelled flow data. Findings provide support for ‘safety in numbers’: for each increase of a natural logarithmic unit (2.71828) in cycling flows, an 18% decrease in injury odds was found. Conversely, increased motor traffic volume is associated with higher odds of cycling injury, with one logarithmic unit increase associated with a 31% increase in injury odds. Twenty-mile per hour compared with 30mph speed limits were associated with 21% lower injury odds. Residential streets were associated with reduced injury odds, and junctions with substantially higher injury odds. Bus lanes do not affect injury odds once other factors are controlled for. These data suggest that speed limits of 20mph may reduce cycling injury risk, as may motor traffic reduction. Further, building cycle routes that generate new cycle trips should generate ‘safety in numbers’ benefits.

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The Impact of Competitive Quasi-Market on Service Delivery in Benue State University, Makurdi Nigeria

GIS Business ◽

10.26643/gis.v14i4.5120 ◽

2019 ◽

Vol 14 (4) ◽

pp. 85-98

Author(s):

Idoko Peter

Keyword(s):

Service Delivery ◽

A Priori ◽

Least Square ◽

Secondary Source ◽

State University ◽

Ordinary Least Square ◽

Negative Effect ◽

The Impact ◽

The Relationship

This research the impact of competitive quasi market on service delivery in Benue State University, Makurdi Nigeria. Both primary and secondary source of data and information were used for the study and questionnaire was used to extract information from the purposively selected respondents. The population for this study is one hundred and seventy three (173) administrative staff of Benue State University selected at random. The statistical tools employed was the classical ordinary least square (OLS) and the probability value of the estimates was used to tests hypotheses of the study. The result of the study indicates that a positive relationship exist between Competitive quasi marketing in Benue State University, Makurdi Nigeria (CQM) and Transparency in the service delivery (TRSP) and the relationship is statistically significant (p<0.05). Competitive quasi marketing (CQM) has a negative effect on Observe Competence in Benue State University, Makurdi Nigeria (OBCP) and the relationship is not statistically significant (p>0.05). Competitive quasi marketing (CQM) has a positive effect on Innovation in Benue State University, Makurdi Nigeria (INVO) and the relationship is statistically significant (p<0.05) and in line with a priori expectation. This means that a unit increases in Competitive quasi marketing (CQM) will result to a corresponding increase in innovation in Benue State University, Makurdi Nigeria (INVO) by a margin of 22.5%. It was concluded that government monopoly in the provision of certain types of services has greatly affected the quality of service experience in the institution. It was recommended among others that the stakeholders in the market has to be transparent so that the system will be productive to serve the society effectively

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Transport and Chronic Injuries Caused by Improper Use of Cell Phones：Evidences from 41 Studies (Preprint)

10.2196/preprints.21313 ◽

2020 ◽

Author(s):

Xinxi Cao ◽

Yangyang Cheng ◽

Chenjie Xu ◽

Yabing Hou ◽

Hongxi Yang ◽

...

Keyword(s):

Human Body ◽

Cell Phone ◽

Injury Risk ◽

Negative Impact ◽

Mental Disease ◽

Cell Phones ◽

Cell Phone Use ◽

Improper Use ◽

Chronic Injuries ◽

The Impact

BACKGROUND Cell phone use brought convenience to people, but using phones for a long period of time or in the wrong way and with a wrong posture might cause damage to the human body. OBJECTIVE To assess the impact of improper cell phone use on transport and chronic injuries. METHODS Studies were systematically searched in PubMed, EMBASE, Cochrane, and Web of Science up to April 4, 2019 and relevant reviews were searched to identify additional studies. A random-effects model was used to estimate the overall pooled estimates. RESULTS Cell phone users were at a higher risk for transport injuries (RR: 1.37, 95%CI: 1.221.55), long-term use of cell phones increased the transport injury risk to non-use or short-term use (RR: 2.10, 95% CI: 1.632.70). Neoplasm risk caused by cell phone use was 1.07 times that of non-use (95% CI: 1.011.14); Compared with non-use, cell phone use had a higher risk of eye disease, with a risk of 2.03 (95% CI: 1.273.23), the risk of mental disease was 1.26 (95% CI: 1.171.35), the risk of neurological disorder was 1.16 (95% CI: 1.021.32), and a pooled risk of other chronic injuries was 1.20 (95% CI: 0.981.59). CONCLUSIONS Cell phone use at inappropriate situations has a negative impact on the human body. Therefore, it is necessary to use cell phones correctly and reasonably.

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Frame me if you must: PrEP framing and the impact on adherence to HIV Pre-exposure Prophylaxis

Open Forum Infectious Diseases ◽

10.1093/ofid/ofx163.1113 ◽

2017 ◽

Vol 4 (suppl_1) ◽

pp. S439-S439

Author(s):

Eric Ellorin ◽

Jill Blumenthal ◽

Sonia Jain ◽

Xiaoying Sun ◽

Katya Corado ◽

...

Keyword(s):

A Priori ◽

Social Groups ◽

Continuous Measure ◽

Gay Community ◽

Randomized Controlled ◽

Exposure Prophylaxis ◽

The Impact ◽

Actual Prevalence ◽

Tenofovir Diphosphate

Abstract Background “PrEP whore” has been used both as a pejorative by PrEP opponents in the gay community and, reactively, by PrEP advocates as a method to reclaim the label from stigmatization and “slut-shaming.” The actual prevalence and impact of such PrEP-directed stigma on adherence have been insufficiently studied. Methods CCTG 595 was a randomized controlled PrEP demonstration project in 398 HIV-uninfected MSM and transwomen. Intracellular tenofovir-diphosphate (TFV-DP) levels at weeks 12 and 48 were used as a continuous measure of adherence. At study visits, participants were asked to describe how they perceived others’ reactions to them being on PrEP. These perceptions were categorized a priori as either “positively framed,” “negatively framed,” or both. We used Wilcoxon rank-sum to determine the association between positive and negative framing and TFV-DP levels at weeks 12 and 48. Results By week 4, 29% of participants reported perceiving positive reactions from members of their social groups, 5% negative, and 6% both. Reporting decreased over 48 weeks, but positive reactions were consistently reported more than negative. At week 12, no differences in mean TFV-DP levels were observed in participants with positively-framed reactions compared with those reporting no outcome or only negatively-framed (1338 [IQR, 1036-1609] vs. 1281 [946-1489] fmol/punch, P = 0.17). Additionally, no differences were observed in those with negative reactions vs. those without (1209 [977–1427] vs. 1303 [964–1545], P = 0.58). At week 48, mean TFV-DP levels trended toward being higher among those that report any reaction, regardless if positive (1335 [909–1665] vs. 1179 [841–1455], P = 0.09) or negative (1377 [1054–1603] vs. 1192 [838–1486], P = 0.10) than those reporting no reaction. At week 48, 46% of participants reported experiencing some form of PrEP-directed judgment, 23% reported being called “PrEP whore,” and 21% avoiding disclosing PrEP use. Conclusion Over 48 weeks, nearly half of participants reported some form of judgment or stigmatization as a consequence of PrEP use. However, individuals more frequently perceived positively framed reactions to being on PrEP than negative. Importantly, long-term PrEP adherence does not appear to suffer as a result of negative PrEP framing. Disclosures All authors: No reported disclosures.

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319 Validation of the Insomnia Severity Index Short-Form for Identifying Insomnia Disorder in Young Adult Cancer Survivors

SLEEP ◽

10.1093/sleep/zsab072.318 ◽

2021 ◽

Vol 44 (Supplement_2) ◽

pp. A128-A128

Author(s):

Lydia Chevalier ◽

Alexis Michaud ◽

Eric Zhou ◽

Grace Chang ◽

Christopher Recklitis

Keyword(s):

Young Adult ◽

Cancer Survivors ◽

Sensitivity And Specificity ◽

Short Form ◽

A Priori ◽

Severity Index ◽

Young Adult Cancer Survivors ◽

Adult Cancer Survivors ◽

Young Adult Cancer ◽

Insomnia Severity

Abstract Introduction Insomnia is a common and impairing late effect experienced by many young adult cancer survivors (YACS). Although routine evaluation of sleep disorders in cancer survivors is recommended, lack of consensus on appropriate screening measures contributes to under-identification and under-treatment of these disorders in YACS. As screening measures are ideally as brief as possible while maintaining validity, we sought to validate the recently published three-item Insomnia Severity Index Short-Form (ISI-SF) in YACS. Methods 250 YACS completed the ISI and the Structured Clinical Interview for the DSM-5 (SCID-5). The ISI-SF was created by summing three ISI items: distress (item #6), interference (item #7), and satisfaction (item #4). In receiver operating characteristic (ROC) analyses, area under the curve (AUC) was calculated to compare discrimination on the ISI-SF to two criteria: the full-scale ISI using a cutoff of ≥8 recently validated in this sample, and the SCID-5 insomnia module. Consistent with previous research, we specified a priori that a cut-off score on the ISI-SF with sensitivity ≥.85 and specificity ≥.75 would be acceptable. Results The ISI-SF had excellent discrimination when compared to the full-scale ISI (AUC = .97) and a cut-off score of ≥4 met criteria with a sensitivity of 97% and specificity of 86%. The ISI-SF had good discrimination when compared to the SCID-5 (AUC = .88), but none of the cut-off scores met a priori criteria for sensitivity and specificity. A cut-off score of ≥4 came closest with a sensitivity of 94% and specificity of 70%. Conclusion Although the ISI-SF did not meet sensitivity and specificity criteria for a stand-alone screening measure when compared to a diagnostic interview, it demonstrated utility as the first step in a two-step screening procedure. Specifically, the high sensitivity of the ≥4 ISI-F cut-off score is well-suited to accurately screening out YACS who do not need insomnia services; as a second screen, the SCID-5 insomnia module could be administered only to those elevated on the ISI-SF in order to identify false positives cases before making referrals for insomnia specialists. Support (if any) National Cancer Institute (1R21CA223832), Swim Across America

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Using Unstated Cases to Correct for COVID-19 Pandemic Outbreak and Its Impact on Easing the Intervention for Qatar

Biology ◽

10.3390/biology10060463 ◽

2021 ◽

Vol 10 (6) ◽

pp. 463

Author(s):

Narjiss Sallahi ◽

Heesoo Park ◽

Fedwa El Mellouhi ◽

Mustapha Rachdi ◽

Idir Ouassou ◽

...

Keyword(s):

Public Health ◽

A Priori ◽

Epidemiological Models ◽

Sir Epidemic Model ◽

Gulf Region ◽

Epidemiological Modeling ◽

Public Health Policies ◽

Sir Epidemic ◽

The Impact ◽

Case Data

Epidemiological Modeling supports the evaluation of various disease management activities. The value of epidemiological models lies in their ability to study various scenarios and to provide governments with a priori knowledge of the consequence of disease incursions and the impact of preventive strategies. A prevalent method of modeling the spread of pandemics is to categorize individuals in the population as belonging to one of several distinct compartments, which represents their health status with regard to the pandemic. In this work, a modified SIR epidemic model is proposed and analyzed with respect to the identification of its parameters and initial values based on stated or recorded case data from public health sources to estimate the unreported cases and the effectiveness of public health policies such as social distancing in slowing the spread of the epidemic. The analysis aims to highlight the importance of unreported cases for correcting the underestimated basic reproduction number. In many epidemic outbreaks, the number of reported infections is likely much lower than the actual number of infections which can be calculated from the model’s parameters derived from reported case data. The analysis is applied to the COVID-19 pandemic for several countries in the Gulf region and Europe.

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Penalized partial least squares for pleiotropy

BMC Bioinformatics ◽

10.1186/s12859-021-03968-1 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Camilo Broc ◽

Therese Truong ◽

Benoit Liquet

Keyword(s):

Least Squares ◽

Partial Least Squares ◽

Association Studies ◽

A Priori ◽

Simulated Data ◽

Real Data ◽

Genome Wide Association Studies ◽

Genetic Associations ◽

Multiple Traits ◽

Application Fields

Abstract Background The increasing number of genome-wide association studies (GWAS) has revealed several loci that are associated to multiple distinct phenotypes, suggesting the existence of pleiotropic effects. Highlighting these cross-phenotype genetic associations could help to identify and understand common biological mechanisms underlying some diseases. Common approaches test the association between genetic variants and multiple traits at the SNP level. In this paper, we propose a novel gene- and a pathway-level approach in the case where several independent GWAS on independent traits are available. The method is based on a generalization of the sparse group Partial Least Squares (sgPLS) to take into account groups of variables, and a Lasso penalization that links all independent data sets. This method, called joint-sgPLS, is able to convincingly detect signal at the variable level and at the group level. Results Our method has the advantage to propose a global readable model while coping with the architecture of data. It can outperform traditional methods and provides a wider insight in terms of a priori information. We compared the performance of the proposed method to other benchmark methods on simulated data and gave an example of application on real data with the aim to highlight common susceptibility variants to breast and thyroid cancers. Conclusion The joint-sgPLS shows interesting properties for detecting a signal. As an extension of the PLS, the method is suited for data with a large number of variables. The choice of Lasso penalization copes with architectures of groups of variables and observations sets. Furthermore, although the method has been applied to a genetic study, its formulation is adapted to any data with high number of variables and an exposed a priori architecture in other application fields.

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Characteristics of visits and predictors of admission from a paediatric emergency room in Saudi Arabia

BMC Emergency Medicine ◽

10.1186/s12873-021-00467-7 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Mohammad H. Al-Qahtani ◽

Abdullah A. Yousef ◽

Bassam H. Awary ◽

Waleed H. Albuali ◽

Mohammed A. Al Ghamdi ◽

...

Keyword(s):

Saudi Arabia ◽

Hospital Admission ◽

Hospital Admissions ◽

Binary Logistic Regression ◽

Total Sample ◽

Age Group ◽

Chi Squared ◽

Improper Use ◽

Level Shifts ◽

The Impact

Abstract Background The Emergency Repartment (ER) is one of the most used areas in healthcare institutions. Problems with over utilisation and overcrowding have been reported worldwide. This study aims at examining the characteristics of paediatric ER visits, the rate of hospital admissions and its associated predictors at King Fahd Hospital of the University in the Eastern Province of Saudi Arabia. Methods This is a retrospective, medical record-based study. Variables included gender, age group, nationality, complaints, Triage level, shifts and seasons. Descriptive statistics were reported as frequencies/percentages. P-values were obtained through a Chi-Squared test while unadjusted and adjusted odds ratios were estimated by binary logistic regression, where admission was considered as the outcome. Results The total number of paediatric patients included was 46,374, and only 2.5% were admitted. Males comprised 55.4% while females comprised 44.6%. The most common age group were toddlers, and 92.4% of the total sample were Saudis. The most common complaint was fever (26.9%) followed by respiratory symptoms (24.9%). Only 7 patients (0.02%) were classified as triage I (Resuscitation), and most were triage IV (Less urgent) (71.0%). Most visits occurred during the winter months. Adjusted ORs showed that neonates had higher odds of admission (OR = 3.85, 95%CI = 2.57–5.76). Moreover, those presenting with haematological conditions showed an OR of 65.49 (95%CI = 47.85–89.64), followed by endocrine conditions showing an OR of 34.89 (95%CI = 23.65–51.47). Triage I had a very high odds of admission (OR = 19.02, 95%CI = 2.70–133.76), whereas triage V was associated with a very low odds of admission (OR = 0.30, 95%CI = 0.23–0.38). Conclusions A low rate of hospital admission was found in comparison with other rates worldwide. This was mostly attributed to an alarmingly high number of non-urgent ER visits. This further emphasises the problem with improper use of ER services, as these cases should be more appropriately directed towards primary healthcare centres. Further studies to examine the impact of prioritising patients in the ER based on the identified predictors of hospital admission, in addition to the standard triage system, are suggested.

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