67 research outputs found
The international normalized ratio overestimates coagulopathy in patients after major hepatectomy
Abstract BACKGROUND: The International Normalized Ratio (INR) is commonly used to guide therapy after hepatectomy. We hypothesized that the use of thrombelastography (TEG) would demonstrate a decreased incidence of hypocoagulability in this patient population. METHODS: Seventy-eight patients were prospectively enrolled before undergoing hepatectomy. INR, TEG, and coagulation factors were drawn before incision, postoperatively, and on postoperative days 1, 3, and 5. RESULTS: Patients demonstrated an elevated INR at all postoperative time points. However, TEG demonstrated a decreased R value postoperatively, with subsequent normalization. Other TEG measurements were equivalent to preoperative values. All procoagulant factors save factor VIII decreased postoperatively, with a simultaneous decrease in protein C. CONCLUSIONS: TEG demonstrated a brief hypercoagulable state after major hepatectomy, with coagulation subsequently normalizing. The INR significantly overestimates hypocoagulability after hepatectomy and these data call into question current practices using the INR to guide therapy in this patient population. Ó 2014 Elsevier Inc. All rights reserved. Partial hepatectomy remains the treatment of choice for a wide range of both benign and malignant diseases of the liver. Following major hepatectomy, derangement of hepatic synthetic function has been well characterized, including impaired synthesis of serum clotting factors and regulatory proteins
Reuse of measurement plans based on process and quality models
Measurement is needed for project control, quality assurance, and process improvement activities in software development. Measurement planning is a difficult and time-consuming activity. Therefore, a great interest exists in reusing measurement plans. However, most measurement plans are structured intuitively and are written informally. Therefore, they are difficult to understand and to reuse. The contents of measurement plans strongly depend on the object being measured and the quality focus of measurement. Process models (describing the object) and quality models (describing the quality focus) change from project to project and over time. Therefore, in order to reuse measurement plans from one project to the next, relationships between measurement plans and process and quality models are needed. These relationships can be used to identify and adapt existing measurement plans to varying process and quality models. This paper presents a formal conceptual model of measurement plans including relationships to process and quality models and a development process for such measurement plans. This model and process build a sound basis for reuse of measurement plans. To further support reuse, a conceptual model for components of measurement plan elements is sketched. Components can be reused to build new measurement plans. A rudimentary reuse process is proposed that starts from a similarity analysis of the (reused and new) underlying process model and quality models
Kontinuierliche Software-Qualitätsverbesserung in der industriellen Praxis
In der industriellen Praxis werden immer häufiger Verbesserungs- und Meßansätze zur Steigerung der Qualität von Software-Produkten und -Projektdurchführungen diskutiert. Dieser Artikel gibt eine Übersicht über potentielle Ansätze zur kontinuierliche Software-Qualitätsverbesserung:
QIP, CMM und AMI. Aus dem Vergleich der Verbesserungsansätze geht hervor, daß u.a. zielorientiertes Messen eine integrale Technologie zur Verbesserung ist. Deshalb wird in diesem Artikel ein Ansatz für zielorientiertes Messen, der GQM-Ansatz, detaillierter diskutiert. Insbesondere wird auf die Anwendung in der Praxis eingegangen, wobei die Erfahrungen aus realen Projekten in Form von Richtlinien vorgestellt werden. Der Artikel will Praktikern einen Einstieg in die Software Qualitätsverbesserung mittels Messen vermittlen
An Experimental Comparison of the Maintainability of Object-Oriented and Structured Design Documents
This paper presents a controlled experiment focusing on the following issues (i) are object-oriented design documents easier to understand and modify than structured design documents?, (ii) must they comply with quality design principles such as the ones provided by Coad and Yourdon?, and (iii) what is the impact of such design principles on the understandability and modifiability of design documents? Results strongly suggest that such design principles have a beneficial effect on the maintainability of object-oriented design documents. However, there is no strong evidence regarding the alleged higher maintainability of object-oriented design documents over structured design documents. Furthermore, results suggest that object-oriented design documents are more sensitive to poor design practices, in part because their cognitive complexity becomes increasingly unmanageable. However, as our ability to generalise these results is limited, they should be considered as preliminary, i.e., it ..
Practical Guidelines for Measurement-Based Process Improvement
Despite significant progress in the last 15 years, implementing a successful measurement program for software development is still a challenging undertaking. Most problems are not of theoretical but of methodological or practical nature. In this article, we present lessons learned from experiences with goal-oriented measurement. We structure them into practical guidelines for efficient and useful software measurement aimed at process improvement in industry. Issues related to setting measurement goals, defining explicit measurement models, and implementing data collection procedures are addressed from a practical perspective. In addition, guidelines for using measurement in the context of process improvement are provided
Empirical investigation of perspective-based reading: A replicated experiment
Inspection is considered a powerful method to detect defects in a software artifact. It is reported that savings are particularly high if inspections are used in early phases of the software development process, i.e. in the requirements definition phase. However, only few systematic techniques exist to support defect detection in requirements documents. One is perspective-based reading (PBR). The effectiveness of this technique has been validated in an experiment with software professionals at NASA/Goddard Space Flight Center. In this paper we describe a replication of this experiment within an academic environment to validate the original results. In the original experiment, no real team meetings were performed, i.e. the individual results were pooled into nominal team results. In contrast, in our replication effort we performed real team meetings, which allowed us to make a comparison between real and nominal teams. Moreover, we investigated how the technique supports detection of de fects belonging to different defect classes. The results are three-fold: (1) We basically confirm the results of the original experiment, that PBR helps to increase individual and team defect detection effectiveness compared to an Ad-hoc approach. (2) We found no statistically significant difference between real and nominal teams. (3) The analysis according to different defect classes only yield few statistically significant results due to the experimental setting. To document data collection and analysis, we used the Goal/Question/Metric approach. We found it highly beneficial for structuring data collection and analysis especially for replication purposes
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