In studies of radiation from partially coherent sources the so-called quasi-homogeneous (QH) model sources have been very useful, for instance in elucidating the behavior of fields produced by thermal sources. The analysis of the fields generated by such sources has, however, been largely carried out in the framework of scalar wave theory. In this paper we generalize the concept of the QH sourc...

We extend the definition of quasi-finite complexes by considering not necessarily countable complexes. We provide a characterization of quasi-finite complexes in terms of L-invertible maps and dimensional properties of compactifications. Several results related to the class of quasi-finite complexes are established, such as completion of metrizable spaces, existence of universal spaces and a ve...

OBJECTIVES This review aimed to identify the evidence for the efficacy of archwires used in the alignment stage of orthodontic treatment by undertaking a systematic review of the literature. DATA SOURCES MEDLINE, the Cochrane Central Register of Controlled trials (CENTRAL), EMBASE, and the meta Register of Controlled Trials were searched up to July 2008. Reference lists of identified articles...

OBJECTIVE To assess if authors of randomised clinical trials convey the fact that they have used surrogate outcomes and discussed their validity. DESIGN Cohort study. SETTING Six major general medical journals. PARTICIPANTS Randomised clinical trials published in 2005 and 2006 that used a surrogate as a primary outcome. RESULTS Of 626 published randomised clinical trials, 109 (17%) used...

whAt Is the PRoBleM? Different from trials for regulatory approvals of new interventions aimed to test the efficacy, comparative effectiveness research (CER) is the direct comparison of existing health‐care interventions (compared with active controls) to examine which treatment works best, for whom, and under what settings.[1] Therefore, CER is indispensable to assist consumers, clinicians, pu...

The CONSORT (Consolidated Standards of Reporting Trials) Statement aims to improve the reporting of randomized controlled trials (RCTs); however, it lacks guidance on the reporting of patient-reported outcomes (PROs), which are often inadequately reported in trials, thus limiting the value of these data. In this article, we describe the development of the CONSORT PRO extension based on the meth...

This has resulted in the formation of organisations such as the UK Clinical Research Collaboration (www. ukcrc.org). However, in the two years since implementation of the regulations, recruitment into clinical trials in unconscious patients in emergency situations has been slow in the UK. The evidence base for trauma care was already seriously lacking, and the regulations did not help. Unconsci...