Undetected Error Rate Research Articles

The Optimizing Care Model: Final findings of a novel community pharmacy practice model to enhance patient care delivery using technician product verification

BackgroundThe community pharmacy represents a convenient health care access point for patients and is increasingly used to deliver direct patient care services; however, several barriers exist that hinder widespread patient service implementation and scalability. Such barriers include scope of practice restrictions, a dearth of sustainable payment models, lack of pharmacist capacity given other responsibilities, and workflow models developed for dispensing medications rather than clinical care. In an effort to overcome the lack of pharmacist time and capacity, further task delegation to pharmacy technicians has been suggested. ObjectivesThe primary objective of this study was to present the final outcomes of the Optimizing Care Model’s impact. The model’s impact on pharmacist patient care, workday composition, and rates of product selection errors not identified during final product verification are reported. MethodsThe Optimizing Care Model is an innovative approach to community pharmacy practice aiming to foster a new patient-centered care delivery model that expands clinical service delivery and fosters collaboration across health care settings through task delegation, primarily through technician product verification (TPV). To investigate the impact of its sustained implementation, a quasi-experimental, 1-group pretest-posttest design was used. Outcomes assessed included medication errors, clinical activities, and workday composition. ResultsSix chain and 3 independent pharmacies completed the final, continuation phase of the study. Overall pharmacist time spent delivering patient care services increased significantly upon implementation of the Optimizing Care Model (21% vs. 43%; P < 0.05), whereas pharmacist time spent performing dispensing-related activities decreased significantly (67% vs. 37%; P < 0.05). Total undetected error rates were significantly less in the Optimizing Care Model phase compared with the traditional model (0.05% vs. 0.01%; P < 0.001). ConclusionThis study presented the final results of a 2-year assessment of the Optimizing Care Model. Results reaffirmed initial published findings that the model and its use of TPV increase the array and frequency of direct patient care services rendered while resulting in lower undetected error rates. Final project results of the Optimizing Care Model demonstrate increased clinical service delivery versus the traditional model, while also improving patient safety with lower rates of undetected dispensing errors within the Optimizing Care Model. The Optimizing Care Model continues to show promise as a future practice model for community pharmacies.

The Optimizing Care Model: A novel community pharmacy approach to enhance patient care delivery by leveraging the technician workforce through technician product verification

ObjectivesTo explore initial outcomes of the Optimizing Care Model’s impact on patient care through technician product verification after the first 3 months of implementation, including the model’s impact on pharmacist workday composition, rates of patient care services delivered, and rates of product selection errors not identified during final product verification. SettingFourteen chain and independent community pharmacies licensed and located in Tennessee. InnovationThe Optimizing Care Model is an innovative approach to community pharmacy practice aiming to foster a new patient-centered care delivery model that expands clinical service delivery through task delegation to pharmacist extenders. EvaluationA quasiexperimental 1-group pretest–posttest design was used. Study sites self-reported data from 3 months before and 3 months after implementation of the intervention. ResultsOverall pharmacist time spent delivering patient care services increased significantly on implementation of the Optimizing Care Model (25% vs. 43%; P < 0.001), and time spent performing dispensing-related activities decreased significantly (63% vs. 37%; P = 0.02). There was a total increase in quantity of clinical services delivered to patients from baseline, but data from initial study outcomes did not reach statistical significance. At least 1 new clinical service provided under a collaborative practice agreement had been implemented by all 14 sites (100%) as of Spring 2018. Total undetected error rates were significantly less in the Optimizing Care Model phase compared to the traditional model (0.063% vs. 0.085%; P < 0.001). ConclusionInitial results of the Optimizing Care Model demonstrate improved patient care through increased clinical service delivery versus the traditional model. Undetected error detection rates were low in both models, but lower in the Optimizing Care Model. The Optimizing Care Model may represent a novel approach to improving care for patients while creating efficiencies through a staff delegation model, providing pharmacists the opportunity to further evolve their practice and advance clinical care for patients.

Partial CRC-aided decoding of 5G-NR short codes using reliability information

In this paper, we focus on how to further enhance the performance of the channel codes in order to meet the more stringent reliability requirements of future networks (5G and beyond). A general decoder with the aid of partial cyclic redundancy check (CRC) bits is proposed for the polar codes and short low-density parity-check (LDPC) codes in 5G systems.The decoder based on ordered statistic decoding (OSD) method can effectively improve the error-correction performance on the condition that extra CRC bits are used to assist in decoding. Meanwhile, the remaining part of CRC keeps its capability of error-detection to guarantee the undetected error rate low enough.This paper gives the detailed implementation schemes of the partial CRC-aided OSD process and its combination with the conventional decodings of the LDPC/polar codes in 5G systems. The simulation results show our proposed decoding scheme achieves a promising trade-off between the performance gain and the error-detection capabilities.

Analysis on blood scrapping of unqualified alanine transaminase from non-remunerated voluntary blood donors on streets in Dongying City of Shandong Province

Objective To investigate the blood scrapping of unqualified alanine transaminase (ALT) from non-remunerated voluntary blood donors on the streets in Dongying City, Shandong Province, in order to control the ALT undetected error rate of street blood collection points effectively. Methods A total of 12 415 cases blood donors, who volunteered to participate in blood donation on the street in Dongying City from April 2016 to March 2018, were selected as subjects in this study. There were 6 897 cases blood donors who participated in blood donation from April 2016 to March 2017, and 5 518 cases blood donors who participated in blood donation from April 2017 to March 2018. The initial test of ALT in blood samples of blood donors were used dry biochemical method. And the retest of ALT were used kinetic method by automatic biochemical analyzer. According to the results of the initial test and retest of blood samples from blood donors, the initial undetected error rates and scrap rates of unqualified ALT were calculated. According to the distribution of ALT initial undetected error rates of 6 897 cases blood donors who participated in blood donation from April 2016 to March 2017, the rules of ALT initial undetected error was analyzed. And to investigate the effect of control the scrap rate of unqualified ALT of blood collection on the street from April 2017 to March 2018 by the rules of ALT initial undetected errors. Results ① In the study, among the 6 897cases blood donors who participated in blood donation from April 2016 to March 2017, the blood retest results of ALT value from 96 cases blood donors were >50 U/L. The total initial undetected error rate of ALT was 1.38%, and it meant the scrap rate of unqualified ALT was 1.38% too. The initial test results of ALT value in these 96 cases blood donors who undetected in initial test were distributed at the range of 42 U/L≤ALT value≤50 U/L, and mainly concentrated at 47 U/L≤ALT value≤50 U/L, accounting for 77.1%(74/96). For blood donors with the ALT initial test results which was <42 U/L, none of them undetected in the initial test and the undetected error rate was 0. In the 6 897 cases blood donors, the difference in the undetected error rates in different ALT initial test results range were statistically significant (χ2=50.64, P<0.001). And there was a downward trend in the composition ratios of donors in different ALT initial test results range from high to low (χ2trend=85.00, P<0.001). ② In these 5 518 cases blood donors who participated in the blood donation from April 2017 to March 2018, there were 330 cases blood donors whose ALT initial test results were in the range of 42 U/L≤ALT value≤50 U/L, among which 77 cases were found to be inconsistent between initial test and retest results, with the non-conformity rate of 23.3%. There were 5 188 cases blood donors whose ALT initial test results were <42 U/L. And the ALT retest results of these 5 188 cases blood donors were all ≤50 U/L, with the scrap rate of unqualified ALT of 0. Conclusions It can effectively control the unqualified ALT scrap rate at a street blood collection points while the ALT qualification value is set as ALT value<42 U/L. Since this conclusion is based only on the analysis of one single blood sampling point, it is still necessary to verify the conclusion through researches of multiple blood collection points and multiple regions. Key words: Alanine transaminase; Blood safety; Blood scrap; Blood scrap rate; Street blood collection

GA-AdaBoostSVM classifier empowered wireless network diagnosis

Self-healing is one of the most important parts in self-organizing mobile communication network. It focuses on detecting the decline of service quality and finding out the cause of network anomalies and repairing it with high automation. Diagnosis is a particularly important task which identifies the fault cause of problematic cells or regions. To perform the diagnosis, this paper presents two modified ensemble classifiers by using Support Vector Machine (SVM) with different kernels, i.e., SVM with the radial basis function (RBF) kernel (RBFSVM in short) and SVM with the linear kernel (LSVM in short), as component classifier in Adaptive Boosting (AdaBoost), and we call the two ensemble classifiers as Adaptive Boosting based on RBFSVM (AdaBoostRBFSVM in short) and Adaptive Boosting based on linear kernel (AdaBoostLSVM in short). Different with previous AdaBoostSVM classifiers using weak component classifiers, in this paper, the performance of the classifiers is adaptively improved by using moderately accurate SVM classifiers (the training error is less than 50%). To solve the accuracy/diversity dilemma in AdaBoost and get good classification performance, the training error threshold is regulated to adjust the diversity of classifier, and the parameters of SVM (regularization parameter C and Gaussian width σ) are changed to control the accuracy of classifier. The accuracy and diversity will be well balanced through reasonable parameter adjustment strategy. Results show that the proposed approaches outperform individual SVM approaches and show good generalization performance. The AdaBoostLSVM classifier has higher accuracy and stability than LSVM classifier. Compared with RBFSVM, the undetected rate and diagnosis error rate of AdaBoostRBFSVM decrease slightly, but the false positive rate does reduce a lot. It means that the AdaBoostRBFSVM classifier is indeed available and can greatly reduce the number of normal class samples that have been wrongly classified. Therefore, the two ensemble classifiers based on the SVM component classifier can improve the generalization performance by reasonably adjusting the parameters. To set the parameter values of component classifiers in a more reasonable and effective way, genetic algorithm is introduced to find the set of parameter values for the best classification accuracy of AdaBoostSVM, and the new ensemble classifier is called AdaboostSVM based on genetic algorithm (GA-AdaboostSVM in short) (including AdaboostLSVM based on genetic algorithm and AdaboostRBFSVM based on genetic algorithm). Results show that GA-AdaboostSVM classifiers have a lower overall error than AdaboostSVM classifiers. Genetic algorithm could help to achieve a more optimal performance of the ensemble classifiers.

State-of-the-art space mission telecommand receivers

Since their dawning, space communications have been among the strongest driving applications for the development of error correcting codes. Indeed, space-to-Earth telemetry (TM) links have extensively exploited advanced coding schemes, from convolutional codes to Reed-Solomon codes (also in concatenated form) and, more recently, from turbo codes to low-density parity-check (LDPC) codes. The efficiency of these schemes has been extensively proved in several papers and reports. The situation is a bit different for Earth-to-space telecommand (TC) links. Space TCs must reliably convey control information as well as software patches from Earth control centers to scientific payload instruments and engineering equipment onboard (O/B) spacecraft. The success of a mission may be compromised because of an error corrupting a TC message: a detected error causing no execution or, even worse, an undetected error causing a wrong execution. This imposes strict constraints on the maximum acceptable detected and undetected error rates.

Analysis and performance evaluation of new coding options for space telecommand links ‐ Part I: AWGN channels

SummaryWe investigate and compare, over the additive white Gaussian noise channel, different options for updating the error correcting code currently used in space mission telecommand links. Besides some more consolidated proposals, using low‐density parity‐check codes, we characterize and assess the performance of alternative schemes, based on parallel turbo codes and soft‐decision decoded Bose‐Chaudhuri‐Hocquenghem (BCH) codes. The analysis considers relevant metrics like the codeword error rate, the frame error rate, and the undetected frame error rate. The considered codes include binary and non‐binary low‐density parity‐check codes, parallel turbo codes and extended BCH codes, with different decoding algorithms. The complexity of the various schemes and possible limits for their application are considered and discussed. Several numerical examples are provided. International Journal of Satellite Communications and Networking. Copyright © 2014 John Wiley &amp; Sons, Ltd.

Reducing Undetected Error Rate of CRC Coding Based on Lossless Compression and Implement in Circuits

循环冗余校验(CRC)算法在很多领域都有广泛的应用。对于确定格式的CRC校验码生成多项式，其错误漏检率基本为确定值。因此待检数据的长度越大，出现错误而不会被检测到的机会也就越多。为了解决这方面存在的问题，该文利用无损压缩霍夫曼算法缩短待测数据的长度，从而降低了数据出错之后不能被检测到的概率。并设计出相应的可靠性校验电路。与单纯使用CRC校验的方法相比，该文提出的方法可以将出错的几率下降为原来的万分之一以下。设计得到的电路模块可以作为VLSI中的可靠性电路模块(IP)加以利用。

A family-based association study of congenital left-sided heart malformations and 5,10 methylenetetrahydrofolate reductase.

Aortic valve stenosis (AVS), coarctation of the aorta (CoA), and hypoplastic left heart syndrome (HLHS) are obstructive malformations of the left ventricular outflow tract that account for a significant proportion of infant mortality. Two previous small case-control studies suggested methylenetetrahydrofolate reductase (MTHFR) polymorphisms may be associated with this group of malformations. We used a family-based association design with inclusion criteria of nonsyndromic diagnosis of AVS, CoA, and HLHS, powered to detect an odds ratio for the heterozygote of <1.5. A total of 207 affected offspring-parent trios were genotyped by restriction fragment length polymorphisms at the two common polymorphic loci C677T and A1298C. Error rate estimation based on replicate samples was 0.76%. Mendelian inconsistency at either polymorphism was noted in 10 trios, for a calculated undetected error rate of 1.95%. A total of 197 trios were analyzed using the transmission disequilibrium test. Significant association was not found between both the C677T or A1298C polymorphisms and presence of a heart defect, whether analyzed as a group, or by sex, ethnicity, or specific diagnosis. A log-linear analysis did not find increased relative risk based on the maternal genotype. We were unable to replicate previous association studies and concluded that neither the affected nor the maternal MTHFR genotype, by itself, is a major risk factor for congenital left ventricular outflow tract malformations.

Reed-Solomon decoding algorithms for digital audio broadcasting in the AM band

Digital audio broadcasting (DAB) systems for the AM band are being developed to provide higher-quality radio broadcasts, broader coverage, and data services. Transmission is typically done by means of multistreaming with QAM/OFDM in the high bits/sec/Hz regime in which Reed-Solomon codes, either alone or in concatenation with inner trellis coded modulation (TCM), are natural choices for error control. For the AM DAB application, Reed-Solomon codes with suboptimal decoders of the bounded-distance type offer error correction important for bringing down the error probability, but also offers error detection important for generating block detected-error flags for use in the error concealment, or error mitigation, algorithm in the audio decoder. For multistream systems, the block detected-error flags can also be used to select the component streams retained by the audio decoder. In this paper, we evaluate the performance of Reed-Solomon codes in terms of both detected (flag) and undetected error rates for DAB applications. We provide simulation results for a variety of decoding algorithms, including hard-decision decoding (HDD), successive-erasure decoding (SED), and fixed-erasure decoding (FED), and discuss the channel environments in which each of these algorithms may be appropriate. Among other results, for example, we address the issue of matching the blocklength of the Reed-Solomon code to the audio decoder with its variable frame structure. From our simulation results for HDD, we conclude that the increased error correction capability of longer Reed-Solomon codes more than compensates for the mismatch in terms of error mitigation in the audio decoder. We also observe that SED provides only small improvements for uniform interference channels, while FED offers considerable improvements for some partial-band interference channels. We describe an appealing two-mode adaptive configuration using HDD and FED for mitigating partial-band interference caused by some second-adjacent AM broadcasts.

Design of error correction systems for disk drives

Certain models are presented for analysis of Reed-Solomon (R-S) error correction systems in the context of optimizing their use in magnetic and optical disk storage devices. A brief statement of design considerations is noted with references as to which considerations are addressed by the models. This work is motivated by the desire to achieve the highest possible storage density within the constraints of user requirements (acceptable error rates, performance, etc.), recording code, recording channel, read channel, and cost. One pair of models treats conversion of soft error rates and burst length distributions from the read channel into hard bit error rates for various levels of interleaving. Another model, using the above models, conservatively estimates undetected bit error rate (miscorrection bit error rate). This model is closer to simulation examples than the previously published McEliece-Swanson bound. A third model includes effect of TAs (thermal asperities) on hard bit error rate. A fourth set of models includes the effect of thermal asperities (TAs) on an undetected bit error rate. Collectively, these models provide a bridge between read channel portions of data storage systems and error correction systems. A fifth set of models addresses user-perceived performance. Finally, an example is offered based upon one set of sample data to show how the models can be applied to help select an optimum system.

Error characteristics of fiber distributed data interface (FDDI)

An analysis is made of the impact of various design decisions on the error detection capability of the fiber distributed data interface (FDDI), a 100-Mb/s fiber-optic LAN standard being developed by the American National Standards Institute (ANSI). In particular, the frame error rate, token loss rate, and undetected error rate are quantified. Several characteristics of the 32-b frame check sequence (FCS) polynomial, which is also used in IEEE 802 LAN protocols, are discussed. The standard uses a nonreturn to zero invert on ones (NRZI) signal encoding and a 4-b to 5-b (4b/5b) symbol encoding in the physical layer. Due to the combination of NRZI and 4b/5b encoding, many noise events are detected by code (or symbol) violations. A large percentage of errors are detected by FCS violations. The errors that escape these three violations remain undetected. The probability of undetected errors due to creation of false starting delimiters, false ending delimiters, or merging of two frames is analyzed. It is shown that every noise event results in two code bit errors, which in turn may result in up to four data bit errors. The FCS can detect up to two noise events. Creation of a false starting delimiter or ending delimiter on a symbol boundary also requires two noise events. This assumes enhanced frame validity criteria. The author justifies the enhancements by quantifying their effect.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Error Detection in the Presence of Synchronization Loss

Cyclic codes are very attractive for error detection because of their low cost encoding and decoding circuits, and because of their high guaranteed minimum distance, but they suffer from very poor protection when word frame synchronization is lost. This note suggests starting the encoder and decoder circuits in an essentially random state, instead of the usual all-zero state. Under this condition of operation it is shown that the undetected error rate against synchronization loss is 2^{-p} where p is the number of parity check bits.

Buffer Management for Sequential Decoding

Sequential decoding has been found to be an efficient means of communicating at low undetected error rates from deep space probes, but another failure mechanism known as erasure or computational overflow remains a significant problem. The erasure of a block occurs when the decoder has not finished decoding that block at the time that it must be output. The erasure rate can be unacceptably high even when the decoder is spending over half of its time idly awaiting incoming data. By drawing upon analogies in computer time sharing, this concise paper develops a buffer-management strategy which reduces the decoder idle time to a negligible level, and therefore improves the erasure probability of a sequential decoder. For a decoder with a speed advantage of ten and a buffer size of ten blocks, operating at an erasure rate of 10-2, use of this buffer-management strategy reduces the erasure rate to less than 10-4.

Comparisons of Error Control Techniques

The performance capabilities of several retransmission systems are compared with each other and with conventional errorcorrecting codes in hypothetical channels exhibiting independent or dependent errors. These evaluations are based on the analysis in the companion paper which admits errors in the feedback channel and undetectable errors in either channel. The basic problem of deciding whether to use retransmission or forward error-correction for a particular application is investigated. The areas of relative superiority based on throughput rate R and uncorrected error rate ρ for each type of error control are determined for a wide range of codes and channels. It is shown that in almost all burst error cases and in independent error channels with low error probabilities, retransmission sytsems are superior to forward error-correcting systems in both throughput rate R and undetected error rate ρ. In independent error channels with high error rates forward error correction shows substantial improvement over retransmission provided that extremely high reliability is not required. It is shown that in designing a retransmission logic, the decision to interpret garbled messages bearing service information as retransmission requests lowers the throughput rate slightly but improves the reliability considerably. The problem of selecting one of the basic retransmission logics for a particular application is also considered. The systems characteristics of the logics were seen to be the prime consideration in many cases since the differences in R and ρ are generally not substantial.

An Analysis of Retransmission Systems

This paper presents an analysis of the throughput rate R and undetected block error rate ρ for each of three basic types of retransmission logics: 1) send and wait for confirmation, 2) send continuously repeating each individual unconfirmed message, and 3) send continuously repeating each unconfirmed message together with those which followed it. Formulas for R and ρ were obtained in terms of the probability of detected block error and the probability of misinterpreted confirmation or retransmission request. Several options for interpreting garbled service information were considered and the corresponding formulas for R and ρ were obtained. Block diagrams are presented which show the possible sequences of events and their probabilities for each type of logic. Analysis of the third logic required models based on seven-state and ten-state Markov processes. Tractable formulas were not obtainable in closed form but only as solutions to matrix equations. Approximate formulas for R and ρ were derived for this case. The results of this paper are used in a companion paper to compare the performance of forward error correcting codes and retransmission systems under various channel conditions.

Effectiveness of Error Control in Data Communication over the Switched Telephone Network

This article describes the results of a data communication experiment designed to investigate the effectiveness of error detection and retransmission in providing high-accuracy data transmission over the switched telephone network. Data were encoded into a Bose-Chaudhuri (31,21) error-detecting code and transmitted at 2000 bits per second by a DATA-PHONE data set 201A over a variety of dialed long-distance connections. Transmitted and received data were compared to obtain error data which were analyzed to obtain an estimate of the error performance of the data set and the effectiveness of the code. The results of this analysis are presented. During the test approximately 6.36 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">7</sup> 31-bit code words or 1.97 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">9</sup> bits were transmitted. Of these, 63,002 bits appearing in 29,731 different code words were received incorrectly. Thus, the over-all bit error rate was 3.19 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−5</sup> and the word error rate 4.67 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−4</sup> . The decoder was successful in detecting all but two of the erroneous code words, resulting in an average undetected word error rate of 3.14 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−8</sup> or an average of 9.85 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">8</sup> bits between undetected word errors. These results demonstrated that very low undetected error rates can be obtained in practice using an error detection and retransmission system of modest complexity.