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Purpose
Measurement invariance issues should be considered during test construction. In this paper, we provide a conceptual overview of measurement invariance and describe how the concept is implemented in several different statistical approaches. Typical applications look for invariance over things such as mode of administration (paper and pencil vs. computer based), language/translation, age, time, and gender, to cite just a few examples. To the extent that the relationships between items and constructs are stable/invariant, we can be more confident in score interpretations.Methods
A series of simulated examples are reported which highlight different kinds of non-invariance, the impact it can have, and the effect of appropriately modeling a lack of invariance. One example focuses on the longitudinal context, where measurement invariance is critical to understanding trends over time. Software syntax is provided to help researchers apply these models with their own data.Results
The simulation studies demonstrate the negative impact an erroneous assumption of invariance may have on scores and substantive conclusions drawn from naively analyzing those scores.Conclusions
Measurement invariance implies that the links between the items and the construct of interest are invariant over some domain, grouping, or classification. Examining a new or existing test for measurement invariance should be part of any test construction/implementation plan. In addition to reviewing implications of the simulation study results, we also provide a discussion of the limitations of current approaches and areas in need of additional research.Areas covered: In this review, we examine data demonstrating the tissue specificity of KIR3DL2 receptor, which is highly expressed on the malignant cells in cutaneous T-cell lymphoma, including mycosis fungoides and Sézary syndrome. This specificity has led to the development of the agent IPH4102. Preclinical data showing efficacy of IPH4102 in vivo are outlined, as well as the results from Phase I clinical trials, which suggest that the agent is both efficacious and well-tolerated. Larger scale clinical trials are to follow.
Expert Opinion: We examine the putative benefit of IPH4102 in comparison to established agents already in the clinic, highlighting its efficacy and relative safety. We also examine possible directions that may better define the role of IPH4102 in the treatment of T-cell lymphoma in the future. 相似文献
Background
Since the Zika virus epidemic in the Americas began in 2015, Zika virus transmission has occurred throughout the Americas. However, limited information exists regarding possible risks of transmission of Zika virus and other flaviviruses through breast feeding and human milk. We conducted a systematic review of the evidence regarding flaviviruses detection in and transmission through milk, specifically regarding Zika virus, Japanese encephalitis virus, tick‐borne encephalitis virus, Powassan virus, West Nile virus, dengue virus, and yellow fever virus.Methods
Medline, Embase, Global Health, CINAHL , Cochrane Library, Scopus, Popline, Virtual Health Library, and WorldCat were searched through June 2017. Two authors independently screened potential studies for inclusion and extracted data. Human and nonhuman (animal) studies describing: 1) confirmed or suspected cases of mother‐to‐child transmission through milk; or 2) the presence of flavivirus genomic material in milk.Results
Seventeen studies were included, four animal models and thirteen observational studies. Dengue virus, West Nile virus, and Zika virus viral ribonucleic acid was detected in human milk, including infectious Zika virus and dengue virus viral particles. Human breast‐feeding transmission was confirmed for only yellow fever virus. There was evidence of milk‐related transmission of dengue virus, Powassan virus, and West Nile virus in animal studies.Conclusions
Because the health advantages of breast feeding are considered greater than the potential risk of transmission, the World Health Organization recommends that mothers with possible or confirmed Zika virus infection or exposure continue to breast feed. This review did not identify any data that might alter this recommendation.The Woven EndoBridge (WEB) device is becoming increasingly popular for treatment of wide-neck aneurysms. As experience with this device grows, it is important to identify factors associated with occlusion following WEB treatment to guide decision making and screen patients at high risk for recurrence. The aim of this study was to identify factors associated with adequate aneurysm occlusion following WEB device treatment in the neurosurgical literature and in our case series. A systematic review of the present literature was conducted to identify studies related to the prediction of WEB device occlusion. In addition, a retrospective review of our institutional data for patients treated with the WEB device was performed. Demographics, aneurysm characteristics, procedural variables, and 6-month follow-up angiographic outcomes were recorded. Seven articles totaling 450 patients with 456 aneurysms fit our criteria. Factors in the literature associated with inadequate occlusion included larger size, increased neck width, partial intrasaccular thrombosis, irregular shape, and tobacco use. Our retrospective review identified 43 patients with 45 aneurysms. A total of 91.1% of our patients achieved adequate occlusion at a mean follow-up time of 7.32 months. Increasing degree of contrast stasis after WEB placement on the post-deployment angiogram was significantly associated with adequate occlusion on follow-up angiogram (p?=?0.005) and with Raymond-Roy classification (p?=?0.048), but not with retreatment (p?=?0.617). In our systematic review and case series totaling 450 patients with 456 aneurysms, contrast stasis on post-deployment angiogram was identified as a predictor of adequate aneurysm occlusion, while morphological characteristics such as larger size and wide neck negatively impact occlusion.
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