Category: Statistics

Traffic Inj Prev. 2023;24(sup1):S124-S130. doi: 10.1080/15389588.2023.2173521.

ABSTRACT

OBJECTIVES: Automated driving (AD) from SAE level 3 onwards represents a paradigm change from human driver controlling the vehicle to a technical system controlling it. In this light, different regulatory bodies (European Commission, Germany, etc.) have defined guidelines for the operation of such a system. One core principle of these guidelines is that the automated operation needs to be at least as safe as human driving-often referred to as the “positive risk balance.” However, these guidelines are general and do not provide details on what this means in a practical sense. This article discusses a method to demonstrate how positive risk balance can be addressed in practice.

METHODS: Starting from a detailed analysis of corresponding guidelines and a literature review of possible risk assessment frameworks, a comprehensive approach has been developed to consider ethical requirements for the development of AD. This approach covers different development stages. The PrOACT-URL (Problems, Objectives, Alternatives, Consequences, Trade-offs, Uncertainty, Risk attitudes, and Linked decisions) approach was chosen for reporting of the work.

RESULTS: The article will present the approach developed by BMW to ensure that a positive risk balance is achieved for an AD system. The approach is presented per development stage (concept phase, AD development phase, verification and validation phase, post-start of production phase). In the concept phase, the scope is to define how good a human driver is and how good an AD needs to be. In the AD development phase, first the relevant system requirements need to be derived. Monte Carlo experiments in combination with Bayesian networks are applied. The fulfillment of these requirements is checked in the verification phase through simulations and test track and real-world tests. For validation of the risk balance, the impact of AD in terms of traffic safety is derived by means of simulation. In the post-start of production phase, field observation is used.

CONCLUSION: The safety of AD is paramount when it comes to its operation and ensuring trust in this technology. The described approach contributes directly to building this trust by considering the principle of a positive risk balance throughout the development in addition to existing safety standards for advance driver assistance systems, such as ISO 26262, ISO21434 or ISO 21488.

PMID:37267019 | DOI:10.1080/15389588.2023.2173521

Traffic Inj Prev. 2023;24(sup1):S111-S115. doi: 10.1080/15389588.2022.2131403.

ABSTRACT

OBJECTIVE: The first automatic emergency braking (AEB) system was presented in 2003 and aimed to mitigate or reduce rear-end crashes. Since then, several AEB systems aimed to reduce other collision types have been introduced and studies have shown that they reduce crash risks. The aim with this study was to evaluate crash reductions of cars fitted with AEB systems with pedestrian detection and those with bicyclist detection.

METHODS: The study is based on the Swedish Traffic Accident Data Acquisition that includes road traffic accidents reported by the police and by emergency hospitals. Crashes occurring between 2015 and 2020 and with cars from model years 2015 to 2020 were included. The statistical analysis used odds ratio calculations with an induced exposure approach where the outcomes of sensitive and nonsensitive crashes were studied. The sensitive crashes were hit pedestrians and bicyclists, respectively. The nonsensitive crash type in both comparisons was struck vehicles in rear-end crashes. Evaluations were also made for different light and weather conditions and for high and low speed roads.

RESULTS: Seven hundred and twelve hit pedestrians and 1,105 hit bicyclists were included, and the nonsensitive crashes consisted of 1,978 vehicles. The overall reduction on crash risk for AEB with pedestrian detection was 8% (±15%; ns) and for AEB with bicyclist detection it was 21% (±17%). When separating for light conditions, no reduction in crash risk for AEB with pedestrian detection nor for AEB with bicyclist detection could be seen in darkness. However, in daylight and twilight conditions, AEB with pedestrian detection reduced pedestrian crash risk by 18% (±19%; ns) and AEB with bicyclist detection reduced bicyclist crash risk by 23% (±19%). No significant reductions could be seen when separating for weather conditions except for a 53% (±31%) reduction for bicyclists in rain, fog, and snowfall. A larger reduction on high-speed roads (50-120 km/h) compared with low-speed roads (10-40 km/h) was also found.

CONCLUSIONS: AEB systems with bicyclist detection were found to reduce the numbers of hit bicyclists, especially in daylight and twilight conditions. In darkness, no reduction for hit pedestrians or bicyclists was found.

PMID:37267014 | DOI:10.1080/15389588.2022.2131403

Traffic Inj Prev. 2023;24(sup1):S9-S15. doi: 10.1080/15389588.2022.2157209.

ABSTRACT

OBJECTIVE: The objectives of this study were to evaluate computationally efficient small female (54.1 kg, 149.9 cm) and midsize male (78.4 kg, 174.9 cm) models with active muscles using volunteer sled test data in a frontal-oblique loading direction and check their response in crash mitigating maneuvers using field test data.

METHODS: The Global Human Body Models Consortium small female (F05-OS+Active) and midsize male (M50-OS+Active) simplified occupant models with active musculature were used in this study. The data from a total of 48 previously published sled test experiments were used to simulate a total of 16 simulations. The experimental study recorded occupant responses of six small female and six midsize male volunteers (n = 12 total) in two muscle conditions (relaxed and braced) at two acceleration pulses representing pre-crash braking (1.0 g) and a low-speed impact (2.5 g). Each model’s kinematics and reaction forces were compared with experimental data. Along with sled test simulations, both of these models were simulated in abrupt braking, lane change, and turn and brake events using literature data. A total of 36 field test simulations were carried out. A CORA analysis was carried out using reaction load and displacement time-history data for sled test simulations and head CG displacement time-history was used for field test simulations.

RESULTS: The occupant peak forward and lateral excursion results of both active models reasonably matched the volunteer data in the low-speed sled test simulations for both pulse severities. The differences between the active and control models were statistically significant (p-value < 0.05) based on the results of Wilcoxon signed-rank tests using peak forward and lateral excursion data. The average CORA scores calculated for the sled test (sled test: M50-OS+Active= 0.543, male control= 0.471, F05-OS+Active= 0.621, female control= 0.505) and field test (M50-OS+Active= 0.836, male control= 0.466, F05-OS+Active= 0.832, female control= 0.787) simulations were higher for active models than control.

CONCLUSIONS: The responses of the F05-OS+Active and M50-OS+Active models were better than control models based on overall CORA scores calculated using both sled and field tests. The results highlight their ability to predict occupant kinematics in crash-mitigating maneuvers and low-speed impacts in the frontal, lateral and frontal-oblique directions.

PMID:37267011 | DOI:10.1080/15389588.2022.2157209

JMIR Form Res. 2023 Jun 2;7:e44806. doi: 10.2196/44806.

ABSTRACT

BACKGROUND: Amidst the COVID-19 pandemic, the traditional health care model has evolved toward a more patient-centric model. In relation to this trend, digital health services have seen an acceleration, which may have significant implications for the health care model. Due to the impact of COVID-19 on health care facilities, it is important to explore health professionals’ willingness to adopt a patient-centric digital health delivery model for medicine and health care.

OBJECTIVE: The aim of this study was to pilot a survey that assesses the impact and implementation of telehealth in view of health care providers prior to and post COVID-19.

METHODS: A total of 26 volunteer health care professionals participated in the pilot study, of which 19/26 (73%) completed the general demographics portion. Among these respondents, 9/26 (35%) completed the entirety of the survey. The questionnaire included questions relating to general demographics, accessibility and benefits, usability, and engagements with telemedicine. Participants were randomly assigned to 1 of the 4 questionnaire designs (A-D) based on their expertise in telehealth. Of the 9 total participants who completed their randomly assigned questionnaire, 1 (11%) was randomly assigned to A, 3 (33%) were randomly assigned to B, 2 (22%) were randomly assigned to C, and 3 (33%) were randomly assigned to D.

RESULTS: Responses and data from the study questionnaire were collected from Qualtrics. Microsoft Excel was used for data organization. Due to limited responses and data, no advanced statistical software was implemented. From the 9 participants who completed the entirety of the survey, responses from those with telehealth experience (n=4) showed that telehealth was preferred for follow-ups, lab results, and consultations, and that with telehealth, there was greater flexibility with appointment times and a decrease in the number of patients seen. Among the 4 health care providers with telehealth experience, all of them believed it improved accessibility and reduced physical barriers; health care professionals believed telehealth reduced translational barriers with patients. Among health care professionals without telehealth experience (n=5), 60% (3/5) reported a decrease in appointments for in-office visits post COVID-19 and strongly agreed or agreed that telehealth could influence the quality of care for patients. All 5 participants also reported no general concerns about telehealth prior to the pandemic and agreed that it would provide accessibility for patients.

CONCLUSIONS: Preliminary findings of our pilot study showed initial support of a dynamical shift within the health care model due to the rise in the use of telehealth services between health care providers and patients but no statistically significant results. Further research and investigation with a larger sample size is warranted to better understand the mindset of health care professionals in adopting telemedicine post COVID-19.

PMID:37266997 | DOI:10.2196/44806

Teach Learn Med. 2023 Jun 2:1-11. doi: 10.1080/10401334.2023.2211967. Online ahead of print.

ABSTRACT

Phenomenon: In 2011, the American Medical Association added a section on professionalism and social media (i.e., e-professionalism) to the Code of Medical Ethics. Given the constantly evolving nature of social media use, research is needed to explore the attitudes and behaviors of current medical students, for most of whom social media has been a central facet of interpersonal communication and society since they were born. The goal of the current study is to examine students’ social media use and attitudes related to online professionalism. Approach: Two-hundred-twenty-two medical students completed a mixed-methods cross-sectional online survey assessing perceptions of professionalism on social media. The survey was informed using the theory of planned behavior and included validated measures of attitudes, norms, and perceived behavioral control related to social media use and online professionalism. We analyzed data using thematic analysis and descriptive statistics and t-tests were conducted using SPSS 26. Qualitative and quantitative data were integrated during the data interpretation phase. Findings: Quantitative results revealed that students had a positive attitude toward having a social media presence as medical students and future physicians. Students reported: positive attitudes toward sharing positive thoughts, posting photos with family members, and posting photos in white coats or scrubs; neutral attitudes toward posting personal and political opinions; negative attitudes toward posting photos with alcohol, commenting about colleagues or the workplace, using profanity, connecting with patients, and commenting about patients. T-tests revealed significant differences between what students consider to be professional online behaviors for themselves as medical students versus what they believe society will expect of them as a physician. Students reported strong perceived behavioral control regarding professional social media behavior. While students reported they would face some difficulty “cleaning up” some previous content, students strongly disagreed that people’s opinions of their online professional image were beyond their control. The qualitative analysis revealed students’ perceptions of (a) what it means to demonstrate “online professionalism,” (b) the challenges they face related to social media, and (c) training and standards related to social media use. Insights: Overall, our study confirms that students would benefit from e-professionalism training that is not merely disciplinary, but offers them evidence-based recommendations for maintaining medical professionalism while also embracing their personal identity and the benefits of social media as a (future) physician. Policies, guidelines, and training programs should constantly evolve as social norms regarding online communication and online identities evolve.

PMID:37266994 | DOI:10.1080/10401334.2023.2211967

Microb Genom. 2023 Jun;9(6). doi: 10.1099/mgen.0.001028.

ABSTRACT

We delineate the evolutionary plasticity of the ecologically and biotechnologically important genus Streptomyces, by analysing the genomes of 213 species. Streptomycetes genomes demonstrate high levels of internal homology, whereas the genome of their last common ancestor was already complex. Importantly, we identify the species-specific fingerprint proteins that characterize each species. Even among closely related species, we observed high interspecies variability of chromosomal protein-coding genes, species-level core genes, accessory genes and fingerprints. Notably, secondary metabolite biosynthetic gene clusters (smBGCs), carbohydrate-active enzymes (CAZymes) and protein-coding genes bearing the rare TTA codon demonstrate high intraspecies and interspecies variability, which emphasizes the need for strain-specific genomic mining. Highly conserved genes, such as those specifying genus-level core proteins, tend to occur in the central region of the chromosome, whereas those encoding proteins with evolutionarily volatile species-level fingerprints, smBGCs, CAZymes and TTA-codon-bearing genes are often found towards the ends of the linear chromosome. Thus, the chromosomal arms emerge as the part of the genome that is mainly responsible for rapid adaptation at the species and strain level. Finally, we observed a moderate, but statistically significant, correlation between the total number of CAZymes and three categories of smBGCs (siderophores, e-Polylysin and type III lanthipeptides) that are related to competition among bacteria.

PMID:37266990 | DOI:10.1099/mgen.0.001028

JMIR Form Res. 2023 Jun 2;7:e45102. doi: 10.2196/45102.

ABSTRACT

BACKGROUND: Physician burnout is a multibillion-dollar issue in the United States. Despite its prevalence, burnout is difficult to accurately measure. Institutions generally rely on periodic surveys that are subject to recall bias. SMS text message-based surveys or assessments have been used in health care and have the advantage of easy accessibility and high response rates.

OBJECTIVE: In this pilot project, we evaluated the utility of and participant engagement with a simple, longitudinal, and SMS text message-based mental health assessment system for physician-trainees at the study institution. The goal of the SMS text message-based assessment system was to track stress, burnout, empathy, engagement, and work satisfaction levels faced by users in their normal working conditions.

METHODS: Three SMS text message-based questions per week for 5 weeks were sent to each participant. All data received were deidentified. Additionally, each participant had a deidentified personal web page to follow their scores as well as the aggregated scores of all participants over time. A 13-question optional survey was sent at the conclusion of the study to evaluate the usability of the platform. Descriptive statistics were performed.

RESULTS: In all, 81 participants were recruited and answered at least six (mean 14; median 14; range 6-16) questions for a total of 1113 responses. Overall, 10 (17%) out of 59 participants responded “Yes” to having experienced a traumatic experience during the study period. Only 3 participants ever answered being “Not at all satisfied” with their job. The highest number of responses indicating that participants were stressed or burnt out came on day 25 in the 34-day study period. There were mixed levels of concern for the privacy of responses. No substantial correlations were noted between responses and having experienced a traumatic experience during the study period. Furthermore, 12 participants responded to the optional feedback survey, and all either agreed or strongly agreed that the SMS text message-based assessment system was easy to use and the number of texts received was reasonable. None of the 12 respondents indicated that using the SMS text message-based assessment system caused stress.

CONCLUSIONS: Responses demonstrated that SMS text message-based mental health assessments are potentially useful for recording physician-trainee mental health levels in real time with minimal burden, but further study of SMS text message-based mental health assessments should address limitations such as improving response rates and clarifying participants’ sense of privacy when using the SMS text message-based assessment system. The findings of this pilot study can inform the development of institution-wide tools for assessing physician burnout and protecting physicians from occupational stress.

PMID:37266985 | DOI:10.2196/45102

Cardiovasc J Afr. 2023 Jun 2;34:1-8. doi: 10.5830/CVJA-2023-004. Online ahead of print.

ABSTRACT

BACKGROUND: Right atrial longitudinal strain (RALS) is a useful parameter to define right atrial (RA) subclinical dysfunction prior to changes in RA dimension and volume. We sought to establish normal values for RALS in a sub-Saharan African population.

METHODS: This was a retrospective, cross-sectional study from 2017 to 2019 of 100 normal individuals. All echocardiographic measurements were done as per the standard guidelines.

RESULTS: Mean RALS was 32.7 ± 10.5%. The mean RA volume indexed to body surface area was 19.5 ± 5.7 ml/m². There was a negative correlation between RALS and age but it was not statistically significant (r = -0.15, p = 0.129). Males had a tendency towards higher RA volume indexed and RALS measurements compared to females (20.8 ± 6.3 and 18.7 ± 5.2 ml/m², p = 0.07; 34.6 ± 9.6 and 31.4 ± 10.9%, p = 0.141, respectively). Body mass index was an independent predictor of RALS (r = -0.43, p = 0.003).

CONCLUSION: We have provided normative data for RALS in an African population. This study provides a platform for future larger studies on RALS.

PMID:37266978 | DOI:10.5830/CVJA-2023-004

Traffic Inj Prev. 2023 Jun 2:1-8. doi: 10.1080/15389588.2023.2218511. Online ahead of print.

ABSTRACT

OBJECTIVES: The paper aims to examine the interdependent relationship between the usage of the seatbelt restraint system and severities of the driver-injury in single-vehicle crashes.

METHODS: This paper developed a comprehensive joint econometric structure – a joint random parameters binary probit-binary probit model – that allows for the simultaneous examination of injury severity of the driver in a crash, and taking into account the fact that seat belt use can be endogenous to the outcomes of driver injury. The developed model is tested using data on drivers-injury severities involved in single-vehicle crashes in Thailand from 2012-2017.

RESULTS: In terms of the interdependent relationship between seatbelt use status and driver-injury severities, the findings suggest that drivers who do not use seat belts may demonstrate more dangerous or aggressive driving behaviors (such as speeding), subsequently increasing their likelihood of involvement in severe or fatal crashes. Additionally, the result also shows that drivers who are involved in speeding-related crashes are less likely to wear a seatbelt and have a higher risk of sustaining severe and fatal injuries. The findings also reveal that in crashes, drivers who are young, or operating trucks are less likely to be wearing their seat belts. The study also indicates that severe and fatal crashes are associated with factors such as elderly drivers, alcohol involvement, unbelted drivers, fatigue, depressed medians, and barrier medians. Conversely, a crash in a U-turn area, driving a passenger car, pickup truck, or large truck, or colliding with a guardrail reduces the likelihood of severe and fatal injuries.

CONCLUSIONS: Neglecting the hidden endogenous effect in statistical analyses could result in an overestimation of the impact of seat belt usage on crash-injury outcomes. The findings of this study can provide valuable insights for relevant authorities aiming to improve driver safety.

PMID:37266974 | DOI:10.1080/15389588.2023.2218511

JAMA Health Forum. 2023 Jun 2;4(6):e231361. doi: 10.1001/jamahealthforum.2023.1361.

NO ABSTRACT

PMID:37266962 | DOI:10.1001/jamahealthforum.2023.1361