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Attenuation corrected myocardial perfusion SPECT (AC-MPS) has been demonstrated to improve the specificity of detecting coronary artery disease (CAD) by visual analysis which utilizes both non-corrected (NC) and AC data. However, the combined automated quantification of NC and AC-MPS has not been previously described. We aimed to develop a combined quantitative analysis from AC and NC data to improve the accuracy of automated detection of CAD from AC-MPS. Stress total perfusion deficit (TPD) values were generated by standard analysis for NC (NC-TPD), AC (AC-TPD) and by combined NC-AC analysis (NA-TPD), in which the hypoperfusion severity in each polar map location was defined as the average of AC and NC severity computed by comparison with separate AC and NC normal limits. Ischemic TPD was also calculated as the difference between stress TPD and rest TPD for each measure. Stress/rest Tc-99m sestamibi MPS studies in 650 patients with correlating coronary angiography and in 345 patients with a low-likelihood (LLk) of CAD were used to assess diagnostic performance of combined NC-AC analysis. NA-TPD had a higher receiver-operator-characteristic area under the curve (ROC-AUC) (0.87) than NC-TPD (0.85; P < .01) or AC-TPD (0.85; P < .01) for detection of stenosis ≥70% in angiographic group. It also had higher specificity (75%) vs NC-TPD (65%; P < .0001), or AC-TPD (70%; P = .016). In LLk group, the normalcy rate of NA-TPD (95%) was higher than for NC-TPD (90%; P < .01) and similar to AC-TPD (94%; P = NS). NA-TPD had higher ROC-AUC than that for 17-segment expert visual scoring of stress scans in angiographic group (0.84; P = .01), comparable accuracy (81%) and similar normalcy rates (95% vs 97%; P = NS). Ischemic TPD by combined NC-AC analysis had higher ROC-AUC than that for any ischemic measure. Similar to stress NA-TPD, it also obtained the similar performance results as compared with ischemic TPD based on NC or AC and higher sensitivity (89% vs 85%; P = .0295) as compared with ischemic visual score in angiographic group. Combined NC-AC MPS quantification using either stress or ischemic TPD shows significant improvements for ROC-AUC and specificity of MPS in the detection of CAD compared with standard NC-MPS or AC-MPS and comparable performance to expert visual scoring. This technique may lead to an enhancement in a fully automated quantification for the perfusion analysis by AC-MPS. [ABSTRACT FROM AUTHOR]

Worldwide losses due to the copyright infringement of intellectual property such as PC software, music recordings, and motion pictures continue at epidemic proportions in emerging countries. This article develops a research model for analyzing individual ethical decision making that is influenced simultaneously by two chief forces: regulative sanction and self sanction. In particular, we report on the differences between 241 U.S. and 277 China college students' self-reported copyright infringement behaviors and attitudes. The analysis shows that the China subjects exhibit less concern about being prosecuted and penalized, but are equally responsive to social sanctions as U.S. subjects, strongly suggesting that stricter enforcement of copyright law in China will reduce copyright violations. However, the results show that self-regulatory efficacy is the primary determinant of copyright adherence for the U.S. subjects. For the China subjects, while self-regulatory efficacy is shown to significantly predict copyright infringement behaviors, it exists at lower levels and plays a lesser role in ethical decision making when compared to the U.S. subjects. Overall, the results indicate that normative and cultural-cognitive changes in China that go beyond regulative enforcement may be required if significant reductions in copyright infringement are to be expected. [ABSTRACT FROM AUTHOR]

Purpose - Few marketing studies look at service classifications for self-service technologies (SSTs) and none directly compare consumer-based perceptions of traditional services to SSTs. To fill this gap, this study aims to examine how customers perceived traditional services and SSTs on service classifications criteria proposed by Lovelock, Bowen and Bell. Design/methodology/approach - In two separate studies consumer ratings for each classification method on each service were obtained. Using multi-dimensional scaling (MDS), 13 traditional services and 12 SSTs were separately mapped onto a perceptual space of service classifications. Findings - The comparison of the two perceptual spaces reveals that consumers viewed the classifications of convenience, person/object, and delivery for SSTs differently than that for traditional services. The classifications of traditional services were represented by two dimensions of customization/ standardization and person/object. In contrast, the classifications of SSTs were represented by two dimensions of customization/standardization and separability/inseparability. Thus the description of the underlying dimensions of services varied by traditional services or SSTs. Research limitations/implications - It is possible that the results of the MDS were influenced by the use of preset classifications. Results may also be influenced by the authors' choice of MDS method. Further research is needed regarding the classification of SSTs and the use of these classifications for SST design. Originality/value - This research extends previous consumer-based classification research by including SSTs. The findings identified separate typologies for SSTs and traditional services. The typologies should be of interest to both researchers and managers who are interested in how SSTs are perceived by consumers. [ABSTRACT FROM AUTHOR]

Abstract This research investigates the premise that purchasing e-banking services is perceived to be riskier than purchasing traditional banking services. Unlike previous studies on perceived risk that typically focused on the relationship of perceived risk and information search, this exploratory study examines the dynamics of perceived risk throughout the various stages of the consumer buying process. A survey of 159 respondents reveals a risk premium for e-banking services that follows a systematic pattern throughout the consumer buying process. When viewed as a dynamic process, perceived risk for e-banking services shows more radical changes in risk levels than traditional banking services. The analyses indicate that financial risk drives the risk premium while psychological, physical and time risk play ancillary roles as risk drivers at certain stages of the consumer buying process. A major implication of this study is that there is a risk premium for e-banking services and the risk premium permeates all stages of the consumer buying process. Risk mitigation strategies are addressed. [ABSTRACT FROM AUTHOR]

EXECUTIVE SUMMARY: With the proliferation of computer-related services, the explosion in data communication,and ongoing trends toward globalization, managers in high-tech industries are considering new ways to manage and control costs. The fact that most Information Technology (IT) services have varied degrees of intangibility makes it a challenge to measure the costs of the services delivered. Activity-based costing (ABC), the alternative to the traditional cost accounting systems, has been applied to manufacturing and service industries. Successful implementations in the healthcare, insurance, and transport industries have been reported over the last few years, but few publications relate ABC to IT. This article reports on a cost management project using ABC modeling focused on an IT division of a publicly held software development firm. The needs of the company to establish accurate recharge rates and define appropriate activities pertinent to business culture were the main driving forces behind the project. The modeling process required the definition of resources, activities, cost objects, and drivers that correspond closely to the organizational functions within the IT division. The resulting model provides a managerial tool to measure productivity and efficiency and is currently being used for IT cost chargebacks and process improvements. Such activities have not been reported in professional publications or activity dictionaries. [ABSTRACT FROM AUTHOR]

This research investigates the premise that the use of Internet airline reservation systems is perceived to be riskier than traditional airline reservation systems. Unlike previous studies on perceived risk that typically focused on the relationship of perceived risk and information search, this study examines the dynamics of perceived risk throughout the various stages of the consumer buying process. A survey of 159 respondents reveals that perceived risk for both traditional and Internet airline reservation services follows a systematic pattern throughout the consumer buying process. Perceived risk for both traditional and Internet airline reservation systems falls during information search but recovers and rapidly increases as consumers approach the moment of purchase. When viewed as a dynamic process, perceived risk for Internet airline reservation services shows more radical changes in risk levels than the traditional service. Another major finding of this study is the discovery of a risk premium for Internet airline reservation services that permeates all stages of the consumer buying process. [ABSTRACT FROM AUTHOR]

Focuses on the hesitation of companies to adopt object-oriented technology. Advantages of object-oriented technology; Reluctance to adopting the technology; Use of organizational learning theory to illuminate the obstacles involved with adopting the technology; Guidelines to help managers mitigate the obstacles.

The audit of computer programs for application control adequacy and compliance is an important EDP audit function involving program testing. Based upon the software reliability literature, statistical techniques for measuring program reliability and determining the theoretical cost of making measurements are reviewed. As an extension of this work, a model is presented that interrelates various internal control factors contributing to program reliability. The model is used to demonstrate the utility of a strong system of internal controls aimed at achieving system reliability. It is argued that software reliability evaluation should be based on assessments of the effectiveness of the organization at monitoring and maintaining its own systems. [ABSTRACT FROM AUTHOR]

The aim of this research was to determine whether presence of atrial fibrillation (AF) provides incremental prognostic information relative to myocardial perfusion single-photon emission computed tomography (MPS) with respect to risk of cardiac death (CD).The prognostic significance of AF in patients undergoing MPS is not known.A total of 16,048 consecutive patients undergoing MPS were followed-up for a mean of 2.21 ± 1.15 years for the development of CD. Of those, 384 patients (2.4%) had AF. Cox proportional hazards method was used to compare clinical and perfusion data for the prediction of CD in patients with and without AF.Atrial fibrillation was a significant predictor of CD in patients with normal (1.6% per year vs. 0.4% per year in non-AF patients), mildly abnormal (6.3% per year vs. 1.2% per year), and severely abnormal MPS (6.4% per year vs. 3.7% per year) (p < 0.001 for all). By multivariable analysis, AF patients had worse survival (p = 0.001) even after adjustment for the variables most predictive of CD: age, diabetes, shortness of breath, use of vasodilator stress, rest heart rate, and the nuclear variables. In the 4,239 patients with left ventricular ejection fraction evaluated by gated MPS, AF demonstrated incremental prognostic value not only over clinical and nuclear variables, but also over left ventricular ejection in predicting CD (p = 0.014).The presence of AF independently increases the risk of cardiac events over perfusion and function variables in patients undergoing MPS. Patients with AF have a high risk of CD, even when MPS is only mildly abnormal. Whether patients with AF and mildly abnormal MPS constitute a group more deserving of early referral to cardiac catheterization is a question warranting further study. [Copyright &y& Elsevier]

: ObjectivesThis study evaluated the prognostic value of transient ischemic dilation (TID) of the left ventricle (LV) in patients with normal stress myocardial perfusion single photon emission computed tomography (MPS).: BackgroundThe prognostic value of TID in patients with an otherwise normal MPS has not been defined.: MethodsWe identified 1,560 patients who had normal stress MPS (436 vasodilator and 1,124 exercise stress), and no rest LV enlargement (Population 1) and followed up for 2.30 ± 0.67 years for hard events (HE) (cardiac death or myocardial infarction) and soft events (SE) (revascularization). Prediction of first HE or SE (total events [TE]) was evaluated by multivariable Cox analysis, which was also applied to a broader group of 2,037 patients (including patients with minimal defects (Population 2).: ResultsIn Population 1, there were 13 HE, 36 SE, and 42 TE. Patients in the highest TID quartile (TID ≥1.21) had a higher TE rate than others, regardless of stress type. By multivariable analysis, highest TID quartile was predictive of TE (p = 0.008). Other independent predictors of TE were age, typical angina, and diabetes. In Population 2, TID was also predictive of TE.: ConclusionsAn entirely normal stress MPS study does not always imply an excellent prognosis. In patients with otherwise normal MPS, TID is an independent and incremental prognostic marker of TE even after significant clinical variables—age, typical angina, and diabetes—are accounted for. When TID is present, caution in making low-risk prognostic statements may be warranted, especially in patients with typical angina, the elderly, and diabetics. Our findings also appear to apply to the broader population of “normal” MPS, which included patients with minimal perfusion defects. [Copyright &y& Elsevier]