基于仿真脑磁共振数据的信噪比在医学影像质量量化上的一致性研究

医学成像过程复杂,且影响成像质量的因素非常多,导致医学影像质量的量化一直非常具有挑战性.信噪比是一种被广泛采用的医学影像质量量化方法,被定义为感兴趣区域的信号均值与背景噪声的标准差的商.它的计算和执行勾画的操作者及勾画的区域密切相关,因此有必要对其一致性进行系统的研究.文章共计使用了324例仿真的磁共振脑影像,分为正常脑和多发性硬化病变两类影像;并将脑脊液区域和白质区域作为感兴趣区域;最后采用Wilcoxon秩和检验来检验操作者间的差异性,并用Pearson相关系数和Spearman秩相关系数来验证感兴趣区域间的一致性.实验结果发现,对相同模态的相同组织区域,不同观察者间的信噪比值没有显著性差异(Wilcoxon秩和检验,P＞0.70);对相同模态的相同观察者,Pearson相关系数rp＞0.71 (P＜10-5),而Spearman秩相关系数_＞0.97 (P＜ 10-3),即信噪比对磁共振影像质量的评价不受操作者以及感兴趣组织的选择而出现差异.进一步的临床数据验证有利于挖掘信噪比在临床应用中的使用条件和潜在局限.     

A Comparative Study on the Implementation Inhibitors and Facilitators of Management Information Systems and Integrated Decision Support Systems: A Perception of IT Practitioners in Mexico

A comparative study of inhibitors and facilitators for implementing management information systems (MIS) and integrated decision support systems (integrated DSS) is reported. Knowing implementation inhibitors and facilitators for a specific IT system is useful for IT practitioners to prepare and use implementation checklists and guidelines when they are confronted with such tasks. In the international literature, several studies have reported implementation critical success factors for a single component of integrated DSS. However, studies on specific inhibitors and facilitators for integrated DSS implementation are still scarce. Consequently, there is very limited and incomplete knowledge about them for DSS implementations. This research addresses this knowledge gap by using collected data from IT practitioners located in medium and large organizations in the central region of an emergent economy (Mexico country), and compares the findings with implementation inhibitors and facilitators for MIS reported in the international literature. Relevant and particular findings suggest critical differences that should be considered for implementing integrated DSS and not treating them as MIS in similar regions of emergent economies. Their utilization in regions of well-developed economies is encouraged to be further studied through a cross-country study.