Actual Safety Research Articles

Application of SWMM model and image recognition in virtual simulation of urban architectural landscape

As the country prioritizes urban water supply issues and water environment, a series of policies have been formulated to manage urban water supply and environmental protection, such as sponge city construction. This article first selects the adaptability study of a city's sponge architecture based on the SWMM model developed by the US Environmental Protection Agency, the overall concept of a city's planning and construction, and watershed water. In today's society, visual recognition technology has been widely used and plays an important role in all aspects. Good recognition technology is the key, and it is of great significance to how to improve the recognition level and recognition speed, which is directly related to the actual performance and safety of visual recognition. In addition, this article focuses on the current structural design and design inefficiency, one-sidedness, and the inability to protect the environment. It also reflects the planning concept for the environment (including people), as well as the process system of building and landscape development, and a brief summary of the virtual simulation technology of the structure. This article selects Sketch Up and 3dsMax for various comparisons for software modeling and design, and combines VR-Platform as a development platform to design and implement virtual 3D vision planning functions. When designing and creating this virtual simulation system, it will mainly focus on four-dimensional landscape, three-dimensional landscape modeling, landscape design and three-dimensional landscape planning.

Actual patient position versus safety models: Specific Absorption Rate implications of initial head position for Ultrahigh Field Magnetic Resonance Imaging.

Specific absorption rate (SAR) relates power absorption to tissue heating, and therefore is used as a safety constraint in magnetic resonance imaging (MRI). This study investigates the implications of initial head positioning on local and whole-head SAR. A virtual body model was simulated at 161 positions inside an eight-channel parallel-transmit (pTx) array. On-axis displacements and rotations of up to 20 mm/degrees and off-axis axial/coronal translations were investigated. Single-channel, radiofrequency (RF) shimming (i.e., single-spoke pTx) and multispoke pTx pulses were designed for seven axial, five coronal and five sagittal slices at each position (the slices were consistent across all positions). Whole-head and local SAR were calculated using safety models consisting of a single (centred) body position, multiple representative positions and all simulated body positions. Positional mismatches between safety models and actual positions cause SAR underestimation. For axial imaging, the actual peak local SAR was up to 4.2-fold higher for both single-channel and 5-spoke pTx, 3.5-fold higher for 3-/4-spoke pTx, and 2-fold higher for RF shimming and 2-spoke pTx, compared with that calculated using the centred body position. For sagittal and coronal imaging, the underestimation of peak local SAR was up to 5.2-fold and 3.8-fold, respectively. Using all body positions to estimate SAR prevented SAR underestimation but yielded up to 11-fold SAR overestimation for RF shimming. Local SAR of single-channel and pTx multispoke pulses showed considerable dependence on the initial patient position. RF shimming yielded much lower sensitivity to positional mismatches for axial imaging but not for sagittal and coronal imaging. This was deemed attributable to the higher degrees-of-freedom of control offered by the investigated coil array for axial imaging. Whole-head SAR is less sensitive to positional mismatches compared with local SAR. Nevertheless, whole-head SAR increased by up to 80% for sagittal imaging. Local and whole-head SAR were observed to be more sensitive to positional mismatches in the axial plane, because of larger variations in coil-tissue proximity. Using all possible body positions in the safety model may become substantially over-conservative and limit imaging performance, especially for the RF shimming mode for axial imaging.

A Spatial Model for Repairing of the Dam Safety Monitoring Data Combining the Variable Importance for Projection (VIP) and Cokriging Methods

The safe operation of dams is related to the lifeline of the national economy, the safety of the people, and social stability, and dam safety monitoring plays an essential role in scientifically controlling the safety of dams. Since the effects of environmental variables were not considered in conventional monitoring data repairing methods (such as the single time series model and spatial interpolation model), a spatial model for repairing monitoring data combining the variable importance for projection (VIP) method and cokriging was put forward in this paper. In order to improve the accuracy of the model, the influence of different combinations of covariates on it was discussed, and the VIPj value greater than 0.8 was proposed as the threshold of covariates. The engineering verification shows that the VIP-cokriging spatial model had the advantages of high precision and strong applicability compared with the inverse distance weighting (IDW) model, the ordinary kriging model, and the universal kriging model, and the overall error can be reduced by more than 60%, which could better realize the expansion of the monitoring effect variable to the whole area of the dam space. The engineering application of the PBG dam showed that the model scientifically correlated the existing monitoring points with the spatial location of the dam, and reasonably repaired the measured values of the stopping and abnormal measured points, effectively ensuring that the spatial regular of the monitoring data could truly reflect the actual safety and operational status of the dam.

Why Do Drivers' Collision Avoidance Maneuvers Tend to Cause SUVs to Sideslip or Rollover on Horizontal Curve and Grade Combinations?-An Analysis of the Causes Based on a Modified Multibody Dynamics Model.

The extent to which drivers' collision avoidance maneuvers affect the safety margins of sideslip and rollover is not captured by road geometric design theory. To quantify the effects of drivers' collision avoidance maneuvers on the safety margins of sport utility vehicles (SUVs) on horizontal curve and grade combinations, a modified 8-degree-of-freedom multibody model based on SUVs was developed. The model was then used to calculate the design safety margins of sideslip and rollover for steady states and the actual safety margins for collision avoidance maneuvers. Subsequently, the design safety margin reduction rate (the difference between the design and actual safety margins divided by the design safety margin) was calculated and used to assess the safety margins. The results showed that the safety margins of SUVs were significantly reduced by braking, lane changing, and lane changing with braking. The marginal effects indicated that the greater the deceleration and the shorter the lane change duration, the greater the effect on the safety margins, particularly the sideslip safety margin. Furthermore, when the SUV was driven at 80 km·h-1 on grades with a horizontal curve radius of 270 m and 400 m, the sideslip safety margin with emergency braking (deceleration over -4.5 m·s-2) was reduced by 71% and 21%, and the rollover safety margin was reduced by 11% and 5%, respectively. Under these conditions, an emergency lane change (lane change duration less than 2 s) caused the SUV to sideslip and reduced the rollover safety margin by 47% (curve radius 270 m) and 45% (curve radius 400 m). Therefore, drivers' collision avoidance maneuvers are a factor that cannot be neglected in alignment design.

Labor rate setting as a framework for enhancing efficiency of mining industry

Production engineering in mines of the Norilsk Division of Norilsk Nickel is experiencing considerable modification. Under conditions of continuous retrofit, production improvement and digitalization and unmanned machinery phase-in, the efficient labor management is a prerequisite of production in a transition period. It is emphasized that the Company’s top managers pay peculiar attention to the primary pitch of the production chain—exploration and extraction of rich ore to be concentrated later on and sent to smelting of nonferrous metals (palladium, nickel, platinum copper, as well as silver and gold). The increase in available ore reserves and the gain in production output are amongst the top priority trends of advancing the Norilsk Division of the Company. The article describes the labor rate setting systems adopted at Norilsk Nickel’s Polar Division and generalizes the experience gained in labor rate setting in the mining industry. The photo chronometry observations are illustrated, and the structure of the work time expenditures and losses is analyzed. The elaborated local regulatory documentation enabled a precision computation of labor force as per the actual labor conditions, labor management and occupational safety at a specific production unit. Labor rate setting almost always entails organizational changes—adjustment of operating regime, shift planning, etc., and is often a catalyzer of innovations to be introduced. Furthermore, labor rate setting enables planning, budgeting and real-time management of operations toward meeting strategic challenges in the today’s business environment.

Illusion of safety? Safety-related perceptions of pedestrians and car drivers around 3D crosswalks

Facilitating safe pedestrian road crossings is a major prerequisite for safe urban environments. In multiple cities around the world, 3D crosswalks have been painted, which provoke an optical illusion, of e.g., a crosswalk floating above the road, in car drivers who approach the crosswalk. However, to date, no detailed study of road users’ safety related perceptions on 3D crosswalks has been conducted. Hence, we investigated car drivers’ and pedestrians’ perceptions of a 3D crosswalk, and how they rate its safety in comparison to traditional (non-3D illusion) crosswalks. In an on-site questionnaire survey, we interviewed 201 pedestrians and 102 car drivers in the direct vicinity of a newly painted 3D crosswalk located in Yangon, Myanmar. Our results show that only 53.9% of the car drivers report to have consciously perceived the 3D effect of the crosswalk. Nonetheless, both, pedestrians and car drivers rate the 3D crosswalk as safer for road crossing than a traditional crosswalk. A high share of pedestrians (43.3%) report taking a detour to use the 3D crosswalk for road crossing. Approximately one third (31.3%) of pedestrians and 48.0% of car drivers interviewed have talked to their friends about the 3D crosswalk, indicating a high potential for using 3D crosswalks as a marketing tool for road safety actors to generate attention for pedestrian safety. Unrelated to our main research question, we found that pedestrians prefer to cross in groups, as it increases the perceived likelihood of cars yielding to them. Overall, the data points to significant increases in the perceived safety of drivers as well pedestrians around the 3D crosswalk. Future studies need to investigate how these perceptions translate to actual safety related behavior.

Comprehensive Evaluation Model of Coal Mine Safety under the Combination of Game Theory and TOPSIS

At present, the frequent occurrence of coal mine accidents in China is a key concern in the field of safety. Although the coal mine accident rate is decreasing due to the progress of technology and the improvement of management, there is still a lack of comprehensive evaluation of the role of various factors in the coal mine. Therefore, the purpose of this study is to establish a game theory combination weight-TOPSIS comprehensive evaluation model based on the analysis of various factors affecting coal mine safety. The model combines the weights obtained from fuzzy analytic hierarchy process (FAHP), entropy weight method (EWM), and back propagation neural network (BP-NN) by using the combination method of game theory and then combines with the TOPSIS method to evaluate 20 indicators in four aspects of a coal mine: personnel, equipment, environment, and management. Taking five mines under Zheng Coal Group as an example, the evaluation results of the game theory combination weight-TOPSIS comprehensive evaluation model are compared with those of the fuzzy analytic hierarchy process and the improved composite weight-TOPSIS method. The results show that the safety grade of the five mine samples under Zhengmei Group is ranked as follows: mine 4 > grade II (relatively safe) > mine 2 > mine 5 > grade III (moderately safe) > mine 3 > mine 1 > grade IV (generally safe). The evaluation result of the game theory combination weight-TOPSIS method is basically consistent with the actual safety situation of the coal mine, which reflects the superiority and practicality of the evaluation model. The model has greater differentiation in the process of determining the coal mine safety grade, and the evaluation results are more intuitive and reasonable, which can provide a more effective evaluation tool for the comprehensive evaluation of coal mine safety. Finally, based on the evaluation results, corresponding policy recommendations to improve the status quo of coal mine safety are proposed, aiming to provide decision-making reference for coal mine safety management personnel.

A Low-Cost and Lightweight Thermal Management System for Lithium-Ion Battery Modules Based on Composite PCM under Normal EV Operating Conditions

In this paper, a novel low-cost and lightweight lithium ion batteries thermal design based on EG-based composite phase change material to store heat under normal EV operating conditions is developed and verified theoretically. The three dimensional thermal simulation model is proposed to compute the transient temperature of the battery at some actual driving conditions during discharge. The capability of battery thermal management system based on composite PCM under four kinds of actual electric vehicles thermal safety evaluation condition is investigated, and some factors influencing the system are discussed in detail. Simulation results show that the temperature of the lithium ion battery can be maintained within a reasonable range by adopting the cooling system. The highest temperature of battery discharging at 1C rate can be kept no more than 45.1 °C in the cost of 0.5mm in thickness and 1.02kg in weight increment of PCM and the temperature consistency evaluation methods based on integral values were proposed. The conclusions got in this paper can be valuable reference for battery thermal management design and analysis of dissipating heat against daily driving discharge condition.

Efficacy and Safety of Pyrotinib in Human Epidermal Growth Factor Receptor 2-Positive Advanced Breast Cancer: A Multicenter, Retrospective, Real-World Study.

PurposePyrotinib, a novel human epidermal growth factor receptor 2 (HER2)-targeted tyrosine kinase inhibitor (TKI), has led to remarkable survival outcomes in HER2-positive advanced breast cancer (ABC) in clinical trials and was approved for second-line standards of treatment for HER2+ ABC in China. However, the clinical trials could not fully reflect reality of clinical practice, and predictive factors were still lacking. This study aimed to assess the actual efficacy and safety of pyrotinib in HER2+ ABC in real-world setting.Patients and MethodsIn this multicenter, retrospective, observational real-world study, we analyzed 171 patients with HER2+ ABC, who received pyrotinib-based treatment from November 2017 to November 2020. The primary end point was progression-free survival (PFS). Secondary end points included overall survival (OS), objective response rate (ORR), clinical benefit rate (CBR) and safety.ResultsUp to November 30, 2021, the median PFS (mPFS) was 12.0 months for all patients. One hundred and sixty-two patients (94.7%) with measurable lesions had been included in efficacy assessment. The ORR and CBR were 45.1% and 81.5%, respectively. A significantly longer PFS was reported in patients who received pyrotinib as first-line treatment, had the ECOG-PS of 0–1, as well as those who were lapatinib-naive. In addition, multivariable analysis indicated that ECOG-PS of 2–4, positive hormone receptor (HR) status, and presence of visceral metastasis were independent negative predictors of PFS. As far as we know, this study first reported the survival outcome of pyrotinib cross-line treatment, with a mPFS of 5.0 months. All grades of adverse events (AEs) occurred in 171 patients (100%), and the most common AE was diarrhea (86.5%).ConclusionThis study further demonstrated the outstanding efficacy and safety of pyrotinib and reported the potential predictors of survival in HER2+ ABC.

Influencing a Culture of Quality and Safety Through Huddles.

Literature shows that interdisciplinary huddles help promote clear communication and proactive reporting of potential errors. High reliability organization (HRO) and just culture models were implemented, yet fragmented team communication about patient safety remained. Huddles were implemented to identify and address patient safety issues. A pre/postintervention design was used. Near-miss and actual event safety metrics, patient satisfaction, and employee satisfaction/work group perceptions were measured at 3 time points over 1 year. Daily interdisciplinary huddles were implemented to improve communication, reduce errors, and improve patient and employee satisfaction. Near-miss reporting increased across time points. Patient satisfaction with how the staff worked together to provide care significantly increased over time. Employee satisfaction and perception of work group communication, collaboration, and psychological safety scores improved, however, were not statistically significant. Implementing huddles demonstrated improved outcomes in patient safety, patient satisfaction, and employee satisfaction/work group perceptions.

Rafi Steel PVL Safety Culture

Abstract: To study and conduct safety audit that the one of reputed esteemed industry of RAFI STEELS PVL, Dindugal. The safety aspects consists of labour safety, Material safety, accident causes, Machinery safety, Ergonomic issues, Hazards identification, and Emergency safety plan. The RAFI STEELS PVL safeties forecasting technique has analysis and find out that if any deviation with compare to actual safety process. The RAFI STEELS PVL safety aspect has learned practically that standard regulation and emergency techniques used in engineering industries. The emergency safety planning and basic safety audits techniques are learned.

Decision-making process and evaluation of public health interventions

RésuméObjectifNous proposons un cadre méthodologique destiné aux experts impliqués dans l'appui à la décision concernant les interventions de santé publique.MéthodesLe cadre méthodologique comprend quatre éléments : 1) une série de neuf questions, formulées en termes non techniques, pertinentes pour juger de l'utilité d'une intervention, considérée à un moment donné dans un contexte donné ; 2) une traduction de ces questions en concepts liés à l'évaluation des interventions (définition de l'intervention, de sa cible et de son objectif, efficacités potentielle et réelle, sécurité, efficience et équité) ; 3) une organisation logique des informations nécessaires pour répondre aux questions ; 4) un algorithme permettant de traduire les informations disponibles en recommandations sur l'utilité réelle de l'intervention dans le contexte où les questions ont été posées.RésultatsChaque étape est illustrée par des questions posées sur des interventions de sécurité routière, le dépistage, la transfusion sanguine et des mesures proposées pendant la pandémie de COVID-19.ConclusionLa décision peut être facilitée si les experts fournissent aux décideurs un résumé formel des forces et faiblesses des connaissances, fondé sur une analyse de toutes les facettes de l'utilité potentielle d'une intervention.

Chinese Consumers' Trust in Food Safety Surveillance Sampling of Commonly Consumed Foods.

In China, food has become safer over the past five years, especially commonly consumed foods. Food supervision sampling has played an important role in improving food safety. However, consumer acceptance of the results of food safety supervision have not kept pace. Communicating actual food safety risks to consumers and improving the public trust in food safety supervision sampling inspection has become an important issue. This study focused on food safety surveillance sampling of commonly consumed foods. In total, 4408 adult consumers were surveyed between August and October 2021. Structural equation modeling was performed for data analysis. This study found significant differences along gender lines and across different cities and levels of education with respect to evaluating competence trust and care trust on food supervision sampling inspection. This study identified the public’s competence trust, care trust, and perception of food safety as factors that significantly affect one’s attitude toward supervision sampling inspection. Care trust showed a more pronounced effect on trust enhancement than competence trust. The present study also provides some practical measures for food safety supervisors to improve public trust in the national food inspection. Specifically, the sampling process should be open and transparent.

SLOPE STABILITY ANALYSIS IN ANDESITE STONE MINING ROLAS NUSANTARA TAMBANG Ltd. IN PASURUAN REGENCY

In mining activities Rolas Nusantara Tambang Ltd. needs to do a slope stability analysis because at that location there has never been a study on the condition of the slopes. In addition, there are several problems that can cause unstable slopes such as slope geometry that is too upright, the presence of discontinuity fields and mining locations that are close to several active volcanoes in East Java, namely Mount Semeru and Mount Bromo so that the potential for earthquakes and vibrations is high and can be affect the stability of the slopes at that location. This study aims to analyze slope stability using the Janbu method in calculating the factor of safety and the Monte Carlo method for the probability of landslides. From the results of the study, the actual slope safety factor (FK) was 1.703 and the probability of landslide (PK) was 0.000% with a slope height of 12 meters and a slope of 850. Then recommendations were given for the overall slope with an overall height of 36 meters and an overall slope of 570, the factor value was obtained. safety (FK) of 2.170 and probability of landslide (PK) of 0.000%. From these results it can be concluded that the slope conditions are in the safe category.

Complexity and Health Technology Safety.

In many ways health technology safety has improved significantly over the past few decades. Yet, we still have examples of incidents where safety of health technology systems of care have led to possible and actual safety incidents. In this paper we examine the complexity of errors in an increasingly complex and digitized system of care. Although safety incidents are decreasing over time due to improvements in the tools used to support care, they still occur. Simple safety incidents prevailed in the 2005. Today, incident reports suggest complexity has emerged as an important issue that needs to be addressed in order to make further healthcare industry safety gains.

Study on Risk of Long-Steep Downgrade Sections of Expressways Based on a Fuzzy Hierarchy Comprehensive Evaluation

The long-steep downgrade sections of expressways are characterized by a large elevation difference, poor horizontal and vertical alignment, and the easy failure of brakes on large trucks. They are sections with a high overall operation safety risk. It is necessary to strengthen the research on traffic risk evaluation. In order to study the traffic safety risks of long-steep downgrade parts of expressways, the fuzzy hierarchical comprehensive evaluation method is used to establish the calculation model. First, an evaluation index system including the target level, rule level, first-level index level and second-level index level is established. The qualitative and quantitative indicators are processed by the set value statistical method and the linear standard method, respectively, so that all indicators can be quantitatively evaluated together. Then, each indicator is assigned a score and divided into five risk levels, and a ridge-shaped fuzzy distribution is used to constitute a membership function for each level. A hierarchical structure model is established with the analytic hierarchy process to determine the affiliation between the upper and lower levels, and the relative weight of each level to the upper level also can be obtained. Finally, according to the hierarchical relevance of each evaluation indicator, a three-level fuzzy comprehensive evaluation model is constructed. The traffic risk evaluation level for long-steep downgrade sections can be obtained, and the probability of the corresponding risk evaluation level can be calculated. Through the risk evaluation of the long-steep downgrade sections of the Fuzhou Yinchuan Expressway in China, this shows that the risk evaluation conclusion obtained by using this evaluation method is consistent with the actual traffic safety situation, which shows that the traffic safety risk evaluation model based on a fuzzy hierarchy comprehensive evaluation is operable.

Flexible battery-free wireless electronic system for food monitoring

Conventional battery powered and rigid wireless electronic systems are needed to be improved for adapting to the actual food quality and safety monitoring. This paper aims to propose and develop a flexible battery-free wireless electronic system (FBES) for food monitoring by the laser direct scribing on commercial polyethylene terephthalate/polyimide/copper (PET/PI/Cu) film. The FBES could acquire the temperature, weighing and pH sensor data, and transmit to the wireless reader by radio frequency identification/near field communication (RFID/NFC) with 13.56 MHz. The FBES could harvest the RF energy from the wireless reader and battery-free power for the food sensors and sensor acquisition module. The surface microscope image of the flexible Cu circuit demonstrated that the laser direct scribing could be easily applied to fabricate the flexible electronic system with low complex process and low cost. The food temperature, moisture loss rate (MLR) and pH monitoring applications have been evaluated. The application evaluation results demonstrated that the proposed FBES has a potential application for many kinds of food monitoring by harvesting the RF energy with continuous or on-demand. It could improve transparency and guarantee the quality and safety of food.

Knowing the safety level of a system in real-time: An extended mathematical model of the STAMP-based RealTSL methodology

The RealTSL methodology is based on STAMP and aims at determining the safety level of complex systems in real-time. RealTSL utilizes accident scenarios derived from STPA, together with: (a) The time durations required between system state transitions, (b) Managerial decisions regarding the sensitivity of the mathematical model, and (c) Real-time system data. This manuscript proposes an extension of the RealTSL mathematical model that allows analysts to distinguish system-level accidents according to their severity, and introduces a new expression of the safety level. In addition, this paper shows how the information contained in the graphical form of the acyclic diagram can be used as an interface so that managers can: (a) Comprehend the current systems state against possible accidents, (b) Interpret the results of the mathematical model, and (c) Help them decide whether mitigation actions are needed. The safety level of a system in time t, therefore, is defined as SL=p→wAi>p→wAj>⋯>p→wAm ordering, where m is the number of system accidents and p→wAi are the most detrimental to safety sequences of safety constraint violations for every accident and ordered according to the severity of their corresponding accidents. The extended mathematical model is demonstrated using a fictitious system, providing a graphic rendition of how unsafe situations progress to accidents through time. This paper aims to open a new perspective in the STAMP literature, on discussions on the problem of measuring what the actual safety level of a system is at a certain moment in time and in a certain context.

The effects of saffron supplementation on the measures of renal function indicators: a systematic review and meta-analysis.

Saffron (Crocus sativus L.) has been proposed as a potential agent to improve renal function in animal studies. But, due to insufficient evidence in human research, further investigation is needed. To fill this knowledge gap, we conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to evaluate the effect of saffron supplementation on the measures of renal function indicators in adults. Renal function was assessed based on serum urea, blood urea nitrogen, and creatinine levels. A systematic search in PubMed/Medline, Scopus, Web of Science, Embase, and Google Scholar databases was done until March 2021 using relevant keywords. A random-effects model was used to estimate the weighted mean difference (WMD) and 95% confidence (95% CI). Nine RCTs were included in the meta-analysis, and their quality was assessed using the Cochrane risk of bias tool. The pooled analysis showed that saffron supplementation had no significant effect on serum urea concentrations (WMD: -1.05mg/dl; 95% CI -5.1 to 3; P = 0.6, I2 = 93%, P < 0.001) and serum creatinine levels (WMD: -0.006mg/dl; 95% CI -0.08 to 0.06; P = 0.8, I2 = 79%, P < 0.001) when compared to the placebo group. In the dose-response analysis, we observed a significant non-linear relationship between the duration of saffron supplementation and serum urea and creatinine levels. Based on our findings, Saffron supplementation had no significant effect on renal function markers, including urea and creatinine. However, further trials are required to determine the actual effect and safety of saffron intervention in human studies. 248081.

Abstract TMP45: Potential For Unwarranted Poor Institutional Patient Safety Scores From Inclusion Of Endovascular Thrombectomy In Us National Ahrq Patient Safety Indicator Program

Introduction: The US Agency of Healthcare Research and Quality (AHRQ) has defined 19 Patient Safety Indicators (PSIs) identifying preventable inpatient events. For endovascular and surgical procedures, PSI-4 is applied: detection of mortality after post-procedural complications of pneumonia, DVT/PE, sepsis, GI hemorrhage, or shock/cardiac arrest. But while a potentially useful metric for elective procedures with expected good outcomes, PSI-4 is also appled to emergent endovascular thrombectomy (EVT) for acute ischemic stroke, which has a high rate of unavoidable fatal outcomes. The appropriateness of PSI-4 for EVT assessment has not been empirically studied. Methods: 1) Systematic literature review to identify comparative rates of unwanted outcomes across all PSIs and diverse endovascular/surgical procedures. 2) Detailed review of consecutive EVT cases at a CSC administratively receiving a PSI-4 safety concern finding by independent non-interventional stroke and neurointerventional experts. Results: The systematic literature review found the overall national event frequency for PSI-4 across all endovascular/surgical procedures was one to several orders of magnitude higher than for the other 18 PSIs, 11.9% vs 0.0004% to 2.1%. Further, within PSI-4, the national event rate for EVT was substantially higher than for general endovascular and surgical procedures, 40.1% vs 11.9%. During a 3-year period from 2016-2018 at the CSC, EVT cases accounted for 11% of neurosurgical PSI-4 findings though they represented only 1.5% of neurosurgical procedures. Detailed analysis of 4 consecutive EVT cases coded as PSI-4 safety events from administrative data per AHRQ algorithms revealed that in all cases patient deaths were actually related to complications of the index stroke, not of the EVT procedure - the cases raised no actual safety concerns. Conclusion: AHRQ Patient Safety Indicator-4 does not identify preventable events among EVT patients and has the potential to misleadingly suggest poor quality of care at hospitals that provide a high volume of endovascular stroke interventions. To avoid unintended consequences of discouraging institutions from pursuing EVT or incorrectly profiling their safety performance, revision of PSI-4 is indicated.