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This document summarizes the contents of the Clinical Guidelines for the Endoscopic Mucosal Resection of Non-Peduncutated Colorectal Lesions that was developed by the working group of the Spanish Society of Digestive Endoscopy (GSEED of Endoscopic Resection). This document presents recommendations for the endoscopic management of superficial colorectal neoplastic lesions. (C) 2017 Elsevier Espana, S.L.U. All rights reserved.

* Abbreviations: CINV — : chemotherapy-induced nausea and vomiting RCT — : randomized controlled trial RSV — : respiratory syncytial virus There are many challenges to be faced when conducting randomized controlled trials (RCTs) in pediatric research. One important challenge is the determination of an appropriate sample size. Recruiting more children than necessary risks unnecessary overexposure of children to an inferior treatment, whereas underestimating the sample required will lead to inconclusive or unreliable results. Both options pose important ethical dilemmas for the pediatric researcher. Reviews have concluded that sample size calculations are frequently based on inaccurate assumptions regarding the key pieces of information needed.1,2 For example, a recent “failed” pediatric RCT highlighted the commonly encountered problem of underestimating the SD of a continuous primary outcome variable.3 This leads to underestimation of the necessary sample size, inadequate statistical power, and, consequently, an unanswered study question. Similarly, an incorrect estimation of the frequency with which a dichotomous outcome, or event, occurs in the control group of a trial (known as the control or baseline event rate) will also lead to incorrect sample size estimation. This standards article uses a series of scenarios to assist pediatric researchers in not only determining an adequate trial sample size but also how to proceed when this sample size may be difficult to achieve. Recommendations for practice are summarized in Table 1. View this table: TABLE 1 Recommendations for Practice Methods to calculate adequate sample sizes are described for superiority, noninferiority, and cluster-randomized trials with various types of primary outcome variables, including continuous, dichotomous, or time-to-event data.4–10 In this article, we focus primarily on superiority trial designs with continuous or dichotomous outcomes. Information on noninferiority or equivalence designs, as well as on cluster-randomized designs, can be found in the literature.9,10 RCTs generally have many outcomes of interest, but the number of patients required (and the main statistical analysis) should be based on … Address correspondence to Martin Offringa, MD, PhD, Senior Scientist and Program Head, Child Health Evaluative Sciences, Research Institute, The Hospital for Sick Children, 555 University Ave, Toronto, Ontario, Canada M5G 1X8. E-mail: martin.offringa{at}sickkids.ca

An earthquake catalog containing a uniform size estimate is important for long-term seismic hazard assessment in regions of low-to-moderate seismicity. During the update of the Earthquake Catalog of Switzerland (ECOS), we performed regression analyses to convert all earthquake size information in ECOS to physically meaningful moment magnitude M-w. For 34 events in and near Switzerland, we determined seismic moment (thus Mw) by regional waveform inversion. Independent Mw estimates for the same events do not exist; however, Mw from European-Mediterranean events, obtained in the same way, agree with M, from Harvard CMT solutions. All other size estimates, M-L, M-D, m(b), M-S, and intensities, are calibrated relative to these 34 events. Teleseismic M-S and m(b) from international data centers are directly regressed against M-w. Most observations in ECOS consist of local magnitudes (ML, MD) and intensities. For local magnitudes, we first calibrated the Swiss Seismological Service's M-L. Then we calibrated magnitudes from observatories in neighboring countries (France, Germany, Italy) using only events in the border region (e.g., France-Switzerland). Modern instrumental records exist only since the mid-1970s. We calibrated the macroseismic dataset, which represents by far the largest period in the catalog, by determining surface wave magnitude M-S for stronger twentieth century Swiss earthquakes from analog seismograms. These M-S, which were converted to M-w, connect intensities and M-w. After calibration, all 20,300 events in ECOS have a unified M-w, including a class-type uncertainty estimate based on the original magnitude scale. ECOS covers the period 250-2001, from 44 degrees N to 51 degrees N and 4 degrees E to 13 degrees E. The largest event in ECOS is the 1356 M-w 6.9 Basle earthquake.

We analysed vertical seismic profiling (VSP) data from two boreholes at Glyvursnes and Vestmanna on the island of Streymoy, Faroe Islands, to determine the magnitude and causes of seismic attenuation in sequences of basalt flows. The work is part of SeiFaBa, a major project integrating data from vertical and offset VSP, surface seismic surveys, core samples and wireline log data from the two boreholes. Values of effective seismic quality factor (Q) obtained at Glyvursnes and Vestmanna are sufficiently low to significantly degrade the quality of a surface reflection seismic image. This observation is consistent with results from other VSP experiments in the North Atlantic region. We demonstrate that the most likely cause of the low values of effective Q at Glyvursnes and Vestmanna is a combination of 1D scattering and intrinsic attenuation due to seismic wave-induced fluid flow within pores and micro-cracks. Tests involving 3D elastic wave numerical modelling with a hypothetical basalt model based on field observations, indicate that little scattering attenuation is caused by lateral variations in basalt structure. © 2007 European Association of Geoscientists and Engineers.