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Nucleated red blood cells (NRBCs) have been studied in critically ill and injured patients as a predictor of increased in-hospital mortality and poor clinical outcomes. While prior studies have demonstrated the prognostic power of NRBCs in the critical patient, there has been a paucity of literature available describing their value as a prognostic indicator in the severely burned patient. This retrospective observational study was conducted from 2012 to 2017. Inclusion criteria for this study included all burn patients with total body surface area > 10% who were aged ≥ 15 years. Demographic and clinical data were collected from the electronic medical record system. Data analysis consisted of descriptive and comparative analysis using SPSS. Two hundred and nineteen patients (17.5%) met inclusion criteria with 51 (23.3%) patients positive for NRBCs. The presence of NRBCs had an increased mortality rate with an odds ratio of 6.0 (P = .001; 2.5, 14.5); was more likely to appear in older patients (P < .001); and was associated with increased hospital length of stay (P < .001), injury severity scores (P < .001), and complications. The presence of NRBCs even at the low concentrations reported in our study showed a 6-fold increase in the rate of mortality. With the current improvements in burn care leading to higher survival rates, the need to improve upon the numerous models that have been developed to predict mortality in severe burn patients is clear given the significantly increased risk of death that the presence of NRBCs portends.

Background Conventional coagulation tests do not provide an accurate representation of the complex nature of trauma induced coagulopathy. Thrombelastography provides a prompt global overview of all dynamic sequential aspects of trauma induced coagulopathy. The objective of this study was to evaluate the impact of using thrombelastography on blood products utilization, crystalloids utilization, hospital, and intensive care using length of stay, and cost savings. Methods We retrospectively reviewed 134 patients (May of 2012 to February of 2015) meeting Class I trauma activation. Outcome data was compared between two groups: patients prior to thrombelastography implementation (n = 87) and patients with thrombelastography guided trauma resuscitation (n = 47). Blood product usage was compared for three time periods: first 4 h, the next 20 h, and first 24 h. Results For the first 24 h of treatment, patients with thrombelastography guided trauma resuscitation had lower packed red blood cells (p = 0.0022) and fresh frozen plasma (p = 0.0474), but higher jumbo pack platelets (p = 0.0476) utilization when compared to the patients prior to thrombelastography implementation. There was no statistical significant difference in the utilization of crystalloids for any of the three time intervals. Patients with thrombelastography guided trauma resuscitation had a shorter hospital length of stay (p = 0.0011) and intensive care unit length of stay (p = 0.0059) than the patients prior to thrombelastography implementation. Cost savings in blood products transfusion were most pronounced in patients with penetrating injuries. Discussion Using visco-elastic tests to guide blood transfusion was first used for liver transplant patients and then applied to cardiovascular surgery and trauma. Similar to other studies, this study showed using visco-elastic tests for trauma patietns corresponded to an overall reduction in the use of packed red blood cells and fresh frozen plasma during the first 24 hours of resuscitation. In addition, this study showed using visco-elastic tests corresponded to a significant reduction in both hospital and intensive care unit length of stay. Conclusion This study demonstrates that Thrombelastography guided trauma resuscitation decreases the overall transfusion requirements of packed red blood cells and fresh frozen plasma. However, given the nature of under-recognized jumbo pack platelets dysfunction in the conventional laboratory parameters, jumbo pack platelets utilization is higher when following Thrombelastography directed resuscitation. The utilization of Thrombelastography corresponded to a reduction in hospital length of stay, intensive care unit length of stay and cost of transfused blood products. Electronic supplementary material The online version of this article (10.1186/s13049-017-0443-4) contains supplementary material, which is available to authorized users.

This paper develops a probability model to evaluate the predictive validity of two-way classification schemes in the context of personal credit scoring and bank loan applications. The Bayesian decision model provides a structure for identifying classification rules that lead to optimal-maximum expected payoff or minimum expected cost-classifications. Using payoffs from multiple perspectives allows identifying conditions where the various perspectives produce contradictory classifications generating either profit premiums or cost penalties depending on the perspective.

The Transportation Security Agency provides airline security in the United States using a variety of measures including a computer based passenger prescreening system. This paper develops Bayesian decision models of two prescreening systems: one that places ticketed passengers into two classifications (fly and no-fly), and a three classification system that includes potential flight. Using a parameterized cost structure, and the expected monetary value decision criteria, this paper develops optimal levels of undesirable personal characteristics that should place people into the various categories. The models are explored from both the government perspective and the passenger's perspective.

This article presents a methodology for measurement systems analysis (MSA) under two conditions.

Measurement error (ME) is the difference between the true unknown value of a variable and the data assigned to that variable during the measuring process. The multiple correlation coefficient quantifies the strength of the relationship between the dependent and independent variable(s) in regression modeling. In this paper, we show that ME in the dependent variable results in a negative bias in the multiple correlation coefficient, making the relationship appear weaker than it should. The adjusted R 2 provides regression modelers an unbiased estimate of the multiple correlation coefficient. However, due to the ME induced bias in the multiple correlation coefficient, the otherwise unbiased adjusted R 2 under-estimates the variance explained by a regression model. This paper proposes two statistics for estimating the multiple correlation coefficient, both of which take into account the ME in the dependent variable. The first statistic uses all unbiased estimators, but may produce values outside the [0,1] int...

[This abstract is based on the author’s abstract.] Standard measurement-system analysis criteria assume a measuring device measures a single product characteristic to determine functionality. In automotive-body manufacturing, however, data are taken f..

This study compared defendants charged with Criminal Sexual Conduct whose victims were

In most cases, manufacturers follow a net build strategy for process development. Functional build represents an integrated approach to product and process development developed by automotive body manufacturers due to the non-rigid nature of sheet metal stampings. This paper proposes a hybrid approach that combines both net build and functional build approaches which results in lower costs than using either method individually. The decision criteria are developed using a Bayesian decision model in the context of purchasing a sheet metal stamping die. The decision rule maps the tool bias to the three actions available to the decision-maker: buy the die, rework the die, and perform a functional evaluation of the panels stamped with the die.

Automobile warranties and thus lifetimes are characterized in the two-dimensional space of time and mileage. This paper presents a non-homogenous Poisson process (NHPP) predictive model for automobile warranty claims consisting of two components: a population size function and a failure or warranty claim rate. The population size function tracks the population in the time domain and accounts for mileage by removing vehicles from the population when they exceed the warranty mileage limitation. The model uses the intensity function of a NHPP—the instantaneous probability of failure—to model the occurrence of warranty claims. The approach was developed to support automobile manufacturers’ process of using claims observed during the early portion (first 7 months) of vehicle life to predict claims for the remainder of coverage, typically between 3 and 5 years. This paper uses manufacturer provided warranty data from a luxury car to demonstrate the NHPP model by predicting claims for three vehicle subsystems. Warranty predictions are then compared with the actual observed values and predictions made with a standard forecasting technique.

A methodology is proposed for approving a measurement system when the variable of interest is not directly measured, but some other related variables are measured to predict the quality characteristic. To approve the measurement system, error must be es..

When using the functional build approach to manufacturing validation during new product development, manufacturers use preproduction assemblies to evaluate whether components within an assembly may build dimensionally correct products. This approach allows some individual component characteristics to not meet their original design specifications, provided the resultant assembly meets its requirements. In applying this functional build methodology, manufacturers assume that the preproduction assemblies provide data representative of what the manufacturer will encounter in the regular production process. This paper evaluates the predictive validity of the functional build approach by utilizing a design of experiment to examine the effect of two factors—build fixture and method of attachment—in constructing functional build preproduction assemblies of stamped sheet metal components. The results confirm the importance of using assembly fixtures that closely resemble regular production processing.

Manufacturers using traditional process control charts to monitor their sheet metal stamping pro- cesses often encounter out-of-control signals indicating that the process mean has changed. Unfortunately, a sheet metal stamping process does not have the necessary adjustability in its process variable input settings to allow easily correcting the mean response in an out-of-control condition. Hence the signals often go ignored. Accord- ingly, manufacturers are unaware of how much these changes in the mean inflate the variance in the process output. We suggest using a designed experiment to quantify the variation in stamped panels attributable to changing means. Specifically, we suggest classifying stamping variation into three components: part-to-part, batch-to-batch, and within batch variation. The part-to-part variation represents the short run variability about a given stable or trending batch mean. The batch-to-batch variation represents the variability of the individual batch mean between die setups. The within batch variation represents any movement of the process mean during a given batch run. Using a two-factor nested analysis of variance model, a manufacturer may estimate the three components of variation. After partitioning the variation, the manufacturer may identify appropriate countermeasures in a variation reduction plan. In addition, identifying the part-to-part or short run variation allows the manufacturer to predict the potential process capability and the inherent variation of the process given a stable mean. We demonstrate the methodology using a case study of an automotive body side panel.

Manufacturers and suppliers use quality measures calculated from dimensional data to make informed decisions regarding measurement systems and product quality. Many manufacturers and suppliers use the precision-to-tolerance ratio—scaling the standard deviation of gage error (σg) by the design tolerance—to approve a measurement system. Manufacturers and suppliers also use one or more measures of process capability, such as C p that scales the tolerance by the standard deviation of the product (σp), to approve a manufacturing process. A measure used to assess the ability for two parties to communicate via dimension data is the correlation in repeat measurements that we derive as a function of σg and σp. By plotting the precision-to-tolerance ratio and the correlation in repeat measurements on the σg and σp axes, acceptable and nonacceptable regions for measurement systems are defined. When we add C p (a measure of process capability) to the mix, a relationship between the three measures suggests a method fo...

The knowledge economy and explosion of information technology have resulted in many computer-based workers who experience discomfort, cumulative trauma disorders, and tend to have a higher body mass index than manufacturing workers. The process of redesigning workstations to address these issues should include a study that evaluates the impact on productivity. This paper demonstrates that productivity evaluations of potential designs can utilize simple low-cost methods by assessing productivity with an input task based on Fitts’ Tapping test. This research compares three computer workstation designs (seated, standing and walking) and shows that walking adversely affects productivity yet comparing seated and standing postures yields mixed results. For more simple tasks, the ideal posture is sitting while for more complex tasks the worker should be standing for improved productivity.

This paper suggests evaluating field performance by analyzing hazard plots of the random variable time to first warranty claim. This approach corrects biases that arise when a single member contributes many repairs to the repair population and allows comparing the empirical lifetime distribution with the parametric model assumed at product design (e.g., Exponential or Weibull). Using automobile warranty data we demonstrate how using too broad a scope can mitigate changes in field performance by aggregating improving and degrading components. When comparing warranty performance across model years, the analyst should adjust the hazard plots to reflect common field service time.

Background Owing to the potential risks associated with missed injury, many blunt trauma patients with suspected cervical spine injury undergo some form of imaging technique which has progressed from primarily using plain radiography to relying on CT. Recently, studies have shown that in certain situations, adding MRI may improve the diagnostic accuracy over solely relying on CT. Methods Retrospective study of 3468 adult blunt trauma patients at a level I trauma center of which 94 with an initial negative CT scan underwent subsequent MRI. These 94 patients were classified as reliable or unreliable for examination; coded as either having a positive or negative MRI result; and assessed for a change in management. Results Of the 94 patients in the study population, 69 (73.4%) were deemed reliable and 25 (26.6%) deemed unreliable for examination. Overall, 65 (69.1%) patients had a positive MRI result—49 (71.0%) reliable and 16 (64.0%) unreliable—with some patients testing positive for more than one finding. There was no significant difference in positive MRI rates between reliable and unreliable patients. None of the 29 patients who had negative MRI had a change in management, while 31 of the 65 (47.7%) patients with positive MRI did have a change in management of either continued cervical collar immobilization or neck surgery. Conclusions The use of CT scans should be continued as the primary imaging technique for patients with suspected cervical spine injuries. In cases where obtundation or clinical suspicion exists for a false-negative CT scan, MRI should be considered as a supplement and should not be rejected solely based on the negative result of the CT. Level of evidence Level IV.

Medical professionals, physical therapists, product designers, and computational models all use cervical spine range of motion reference values. To support these functions, researchers have collected a plethora of data to determine the normal range of motion of the cervical spine of adult subjects. However, little to no data exists for subjects under the age of 14. This study utilized the cervical range of motion device, referenced with respect to the Frankfort Plane, to measure the active cervical spine range of motion in all three cardinal planes of the human body, for 106 subjects whose ages ranged from 8 to 10 years. The active range of motion for flexion, extension, lateral extension, and rotation was calculated as 66+/-13 degrees , 85+/-14 degrees , 58+/-8 degrees , and 77+/-7 degrees , respectively, using linear statistics. The observed data significantly differed from the published American Medical Association guidelines for adults but fell within the range of the reference values for 10 year olds. Stratifying and analyzing the range of motion data with respect to gender yielded no significant effect. Appendix A analyzes the data using angular statistics, and produces virtually identical results as those from linear statistics.