CheXpert: A Large Chest Radiograph Dataset with Uncertainty Labels and Expert Comparison

Large, labeled datasets have driven deep learning methods to achieve expert-level performance on a variety of medical imaging tasks. We present CheXpert, a large dataset that contains 224,316 chest radiographs of 65,240 patients. We design a labeler to automatically detect the presence of 14 observations in radiology reports, capturing uncertainties inherent in radiograph interpretation. We investigate different approaches to using the uncertainty labels for training convolutional neural networks that output the probability of these observations given the available frontal and lateral radiographs. On a validation set of 200 chest radiographic studies which were manually annotated by 3 board-certified radiologists, we find that different uncertainty approaches are useful for different pathologies. We then evaluate our best model on a test set composed of 500 chest radiographic studies annotated by a consensus of 5 board-certified radiologists, and compare the performance of our model to that of 3 additional radiologists in the detection of 5 selected pathologies. On Cardiomegaly, Edema, and Pleural Effusion, the model ROC and PR curves lie above all 3 radiologist operating points. We release the dataset to the public as a standard benchmark to evaluate performance of chest radiograph interpretation models. The dataset is freely available at https://stanfordmlgroup.github.io/competitions/chexpert .Comment: Published in AAAI 201

A Guide to Writing Letters to the Editor: Expressing Your Opinion to the Public Effectively

One way to express your opinion publicly is through a letter to the editor in your local newspaper. While every letter may not be published, editors pay attention to well-written letters. This is especially true when there are many letters written on the same topic. In turn, elected officials are also influenced by letters newspapers have chosen for publication. This guide will help you prepare an effective letter to the editor that expresses your opinion on an issue. It includes two letters about a controversial issue and specific guidelines on how to prepare a successful letter yourself. After you read the guide, prepare a letter yourself. Let a friend read it for clarity. Be sure to sign the letter and list your address – newspapers will not publish anonymous letters. Your letter can be positive, negative or informative in tone. It can also be emotional or objective. But it should be simple and short – rarely more than 300 words. And, of course, it should reflect your true opinions

A Guide to Writing Letters to Public Officials: Contributing to Important Decisions Affecting You and Others

A well-written personal letter may be the most effective way to communicate with public officials. They want to know how their constituents feel about issues, especially when those issues involve decisions by elected officials. Public officials usually know what lobbying groups are saying about an issue, but often they do not understand how a particular decision affects you. A well-written letter describing your experiences, observations, and opinions may change an official’s mind. The same guidelines are also useful for writing to private officials such as business owners, executives of groups like the chamber of commerce, or presidents of corporate boards of directors. These individuals can also make decisions that affect you or the public. You can write two types of letters – positive or negative. A positive letter explains why a decision is or would be good. You should write positive letters about favorable decisions. A negative letter explains your opposition to a pending decision. Writing effective letters builds your reputation as a thoughtful person in the eyes of officials and makes your criticisms more influential. This guide is designed to help you prepare effective letters. It includes examples of a positive letter and one that criticizes a pending decision. Specific steps for writing an effective letter are also described. Then you will write your own letter

A Guide for Personal Testimony: The Art of Using Your Personal Experiences to Influence Policy Decisions

The quality of life in any community is determined to some extent by the laws and policies of governmental units and agencies. One way of changing community conditions is to change the laws and policies. From a group’s perspective, any proposed change may be for the better or the worse. However, for changes in laws, regulations, or policies to occur, a public hearing is often required. During public hearings, people have an equal opportunity speak either for or against proposed changes. Many different types of testimony can be and usually are provided during public hearings. These may range from detailed, expert testimony using facts and figures to brief, personal testimony using personal experiences. Each type of testimony has great importance, because public officials often judge the importance of an issue by the number and type of comments they hear. The purpose of brief, personal testimony is to help those making the decision understand the issues in human or personal terms. As someone interested in giving personal testimony, your task is to tell a story about the changes being considered: to tell what they mean to you. This is not an easy task. It is never easy to talk about important things in limited time, and the issues may be very emotional ones. This testimony guide is designed to help you prepare your testimony and to teach you how to present it successfully

Recommendations of the task force on public policy

This is the published version, reproduced here with permission from the publisher. This article is also available electronically from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2741851/.The Task Force on Public Policy was established by the Association for Behavior Analysis to examine ways to encourage members to contribute to policymaking relevant to the public interest. Members discussed issues pertinent to this activity and summarized their discussion in a formal report.' Recommendations of the Task Force for conducting and disseminating policy research and for training, technical assistance, and other services supportive of behavior-analytic research in the public policy arena are presented here

Prevalence and Clinical Significance of HIV Drug Resistance Mutations by Ultra-Deep Sequencing in Antiretroviral-Naïve Subjects in the CASTLE Study

CASTLE compared the efficacy of atazanavir/ritonavir with lopinavir/ritonavir, each in combination with tenofovir-emtricitabine in ARV-naïve subjects from 5 continents.Determine the baseline rate and clinical significance of TDR mutations using ultra-deep sequencing (UDS) in ARV-naïve subjects in CASTLE.A case control study was performed on baseline samples for all 53 subjects with virologic failures (VF) at Week 48 and 95 subjects with virologic successes (VS) randomly selected and matched by CD4 count and viral load. UDS was performed using 454 Life Sciences/Roche technology.Of 148 samples, 141 had successful UDS (86 subtype B, 55 non-B subtypes). Overall, 30.5% of subjects had a TDR mutation at baseline; 15.6% only had TDR(s) at <20% of the viral population. There was no difference in the rate of TDRs by B (30.2%) or non-B subtypes (30.9%). VF (51) and VS (90) had similar rates of any TDRs (25.5% vs. 33.3%), NNRTI TDRs (11.1% vs.11.8%) and NRTI TDRs (24.4% vs. 25.5%). Of 9 (6.4%) subjects with M184V/I (7 at <20% levels), 6 experienced VF. 16 (11.3%) subjects had multiple TAMs, and 7 experienced VF. 3 (2.1%) subjects had both multiple TAMs+M184V, and all experienced VF. Of 14 (9.9%) subjects with PI TDRs (11 at <20% levels): only 1 experienced virologic failure. The majority of PI TDRs were found in isolation (e.g. 46I) at <20% levels, and had low resistance algorithm scores.Among a representative sample of ARV-naïve subjects in CASTLE, TDR mutations were common (30.5%); B and non-B subtypes had similar rates of TDRs. Subjects with multiple PI TDRs were infrequent. Overall, TDRs did not affect virologic response for subjects on a boosted PI by week 48; however, a small subset of subjects with extensive NRTI backbone TDR patterns experienced virologic failure

Public policy-making and research information

provision of behavioral research to policymakers, agenda formation and public policy adoptionDiscusses the types of information that behavioral researchers might provide to public policymakers and how it might be delivered in order to shape public policy. The stages of policymaking, including agenda formation, policy adoption, policy implementation, and policy review, are described. Seven types of research information important in agenda formation and policy adoption are then analyzed. These include information about the dimensions of an issue, number of people affected, relative standing of an issue, interests of those involved, controlling variables, program alternatives, and program acceptability. Methods of communicating research information to policymakers are discussed

Peak Accelerations From the 17 October 1989 Loma Prieta Earthquake

Abstract Peak accelerations of the Loma Prieta main shock have been tabulated from instruments maintained by a number of organizations. We have analyzed a subset of 86 records from nominally free-field sites, which have been subdivided into rock, alluvium, and bay-mud categories according to data available in various reports. After correction for attenuation, the peak accelerations on rock, alluvium, and bay-mud sites are factors of 1.6, 1.8, and 4.5 larger, on the average, than Joyner and Boore’s (1988) predicted values for a M= 6.9 earthquake. The mean motions for the rock and alluvium sites are somewhat greater than one standard deviation away from the predicted value, but the mean acceleration from the bay-mud sites is well outside the range expected from analyses of data from previous earthquakes from rock and alluvium sites. Large amplitudes of motions on bay-mud sites relative to rock sites (a factor of 2.8 for the average of the recordings of the Loma Prieta main shock) has been found previously from recordings of distant earthquakes and explosions, but the Loma Prieta earthquake provided the first opportunity to study the relative amplitudes from strong-motion recordings.</jats:p