BACKGROUND Random errors in measurement of a risk factor will introduce downward bias of an estimated association to a disease or a disease marker. This phenomenon is called regression dilution bias. A bias correction may be made with data from a validity study or a reliability study. AIMS AND METHODS In this article we give a non-technical description of designs of reliability studies with e...

The calculation of the ~23 mixing angle from semi-leptonic B-decay depends’ on the mass ratio m,/mb. The energy scales at which the running masses m, and rnb should be taken are determined once terms of order [cys . (mc/mb)] are taken into account. We give an analytic expression for the QCD correction to the decay rate to all orders in the ratio between on-shell masses. We explain how it should...

A pilot study asks whether something can be done, should the researchers proceed with it, and if so, how. However, a pilot study also has a specific design feature; it is conducted on a smaller scale than the main or full-scale study. In other words, the pilot study is important for improvement of the quality and efficiency of the main study. In addition, it is conducted in order to assess the ...

Background Native T1 mapping is becoming established to help diagnose and monitor myocardial disease. The reproducibility of T1 mapping has not been well characterized, despite the important implications both for interpreting serial clinical studies, and for sample size calculation for surrogate endpoint in clinical trials. The SCMR consensus statement recommends measuring T1 in 2 imaging views...

Data from the first run of the BABAR detector at the PEP II accelerator are presented. Measurements of many rare B decay modes are now possible using the large data sets currently being collected by BABAR. An overview of analysis techniques and results on data collected in 2000 are described.

BACKGROUND Cluster-randomized trials, in which health interventions are allocated randomly to intact clusters or communities rather than to individual subjects, are increasingly being used to evaluate disease control strategies both in industrialized and in developing countries. Sample size computations for such trials need to take into account between-cluster variation, but field epidemiologis...

The speed of digital circuit is one of the most restricting factors in the deep sub-micron and multigigahertz integrated circuits design. It is directly dependent on the circuit delay. Scaling down the technologies and increasing the operational frequency make the delay problems more important. This paper studies the delay in digital circuits, starting from the design process, scaling down the ...

A new algorithm has been proposed to calculate the parameters of full lightning voltage impulses. The new algorithm enables the application of the test voltage factor (also referred to as k-factor in some literatures) for calculation of the equivalent test voltage of impulses with superimposed oscillations/overshoots. The new algorithm at the same time provides a robust procedure for obtaining ...

in the present work, an engineering method is developed to predict laminar and turbulent heating-rate solutions for blunt reentry spacecraft at hypersonic conditions. the calculation of aerodynamic heating around blunt bodies requires alternative solution of inviscid flow field around the hypersonic bodies. in this paper, the procedure is of an inverse nature, that is, a shock wave is assumed a...