bluuebunny/crossref_metadata_2025_split huggingface dataset:
Clinical and Biological Features at Diagnosis in 40 Children With Chronic Myeloid Leukemia
Authors: Millot Frédéric , Traore Philippe , Guilhot Joelle , Nelken Brigitte , Leblanc Thierry , Leverger Guy , Plantaz Dominique , Bertrand Yves , Bordigoni Pierre , Guilhot François 
Published: July 2005

Objective. The purpose of this study was to determine the clinical and biological characteristics at diagnosis in children and adolescents with chronic myelogenous leukemia (CML) in contemporary practice.
Methods. Analysis was conducted on data from 3 prospective trials conducted in children and adolescents with CML. Forty pediatric patients were evaluated in 16 French pediatric oncology units between 1991 and 2003.
Results. The disease predominately affected children who were older than 10 years (67% of the patients), with a higher prevalence in boys than girls (gender ratio: 1.5). Approximately 20% of cases were diagnosed incidentally. The main presenting symptoms were asthenia, weight loss, and complaints related to splenomegaly. Occasional patients presented with signs evocative of leukostasis. Symptoms were more common in patients with splenic enlargement, which was present in 70% of patients, and higher leukocyte counts. Markedly raised leukocyte counts were common (median white blood cell count: 242 × 109/L). The age and the gender of the patients had no effect on the leukocyte count, the hemoglobin level, or the platelet count. A predominance of b3a2 transcript was observed in the 16 children who were studied for the type of chimeric BCR-ABL mRNA.
Conclusions. This is largest reported series of CML at diagnosis in children and adolescents. It shows that the characteristics of CML seem to differ in children compared with previously published adult series; in particular, the presenting leukocyte counts are often higher in children.
Open Access in Primary Care: Results of a North Carolina Pilot Project
Authors: Bundy David G. , Randolph Greg D. , Murray Mark , Anderson John , Margolis Peter A. 
Published: July 2005

Objective.Appointment delays impede access to primary health care. By reducing appointment delays, open access (OA) scheduling may improve access to and the quality of primary health care. The objective of this pilot study was to assess the potential impact of OA on practice and patient outcomes by using pilot-study data from 4 North Carolina primary care practices.Methods.We conducted an interrupted time-series pilot study of 4 North Carolina primary care practices (2 family medicine and 2 pediatric practices) participating in a quality-improvement (QI) collaborative from May 2001 to May 2002. The year-long collaborative comprised 25 practices and consisted of three 2-day meetings led by expert faculty, monthly data feedback, and monthly conference calls. Our main outcome measures were appointment delays, appointment no-shows, patient satisfaction, continuity of care, and staff satisfaction during the 12-month study period.Results.Providers in all 4 practices successfully implemented OA. On average, providers reduced their delay to the third available preventive care appointment from 36 to 4 days. No-show rates declined (first quarter [Q1] rate: 16%; fourth quarter [Q4] rate: 11%; no-show reduction: 5% [95% confidence interval: 1%, 10%]), and overall patient satisfaction improved (Q1: 45% rated overall visit quality as excellent; Q4: 61% rated overall visit quality as excellent; change in satisfaction: 16% [95% confidence interval: 0.2%, 30%]). Continuity of care followed a similar pattern of improvement, but the change was not statistically significant. Staff satisfaction neither improved nor declined.Conclusions.This pilot study suggests that primary care practices can implement OA successfully by using QI-collaborative methods. These results provide preliminary evidence that OA may improve practice and patient outcomes in primary care. These analyses should be repeated in larger groups of practices with longer follow-up.
Prevention and Control of Meningococcal Disease: Recommendations for Use of Meningococcal Vaccines in Pediatric Patients
Authors:   Committee on Infectious Diseases
Published: July 2005

This Policy Statement was retired January 2009.
Two peaks in the incidence of invasive meningococcal disease (IMD) occur in pediatric patients: infants younger than 1 year and adolescents 15 to 18 years of age. Although the incidence of IMD is highest in infants, the case-fatality rate is highest in adolescents (∼20%). Epidemiologic studies also have demonstrated increased risk of IMD among college freshman living in dormitories compared with other college students and similarly aged persons in the general population. At least 75% of cases of IMD in 11- to 18-year-olds are caused by serogroups A, C, Y, and W-135; thus, IMD potentially is preventable by immunization with quadrivalent meningococcal vaccines. Meningococcal A, C, Y, W-135 conjugate vaccine (MCV4) was licensed in 2005 for use in people 11 to 55 years of age. On the basis of data indicating increased risk of meningococcal disease and fatality among certain adolescents and college students, the American Academy of Pediatrics recommends administration of MCV4 to young adolescents (at the 11- to 12-year visit), students entering high school or 15-year-olds, and college freshmen who will be living in dormitories. For pediatric patients 11 years and older who are at increased risk of meningococcal disease, MCV4 also is recommended. The purposes of this statement are to provide the rationale for routine use of MCV4 in adolescents and to update recommendations for use of the meningococcal polysaccharide vaccine in pediatric patients.
Up to equimorphism, hyperarithmetic is recursive
Authors: Montalbán Antonio 
Published: July 2005

AbstractTwo linear orderings areequimorphicif each can be embedded into the other. We prove that every hyperarithmetic linear ordering is equimorphic to a recursive one.On the way to our main result we prove that a linear ordering has Hausdorff rank less thanif and only if it is equimorphic to a recursive one. As a corollary of our proof we prove that, given a recursive ordinal α, the partial ordering of equimorphism types of linear orderings of Hausdorff rank at most α ordered by embeddablity is recursively presentable.
Lexicographic exponentiation of chains
Authors: Holland W. C. , Kuhlmann S. , McCleary S. H. 
Published: July 2005

AbstractThe lexicographic power ΔΓ of chains Δ and Γ is, roughly, the Cartesian power ΠγЄΓΔ totally ordered lexicographically from the left. Here the focus is on certain powers in which either Δ = ℝ or ℚ = ℝ, with emphasis on when two such powers are isomorphic and on when ΔΓ is 2-homogeneous. The main results are:(1) For a countably infinite ordinal (2) ℝℝ ≄ ℝℚ.(3) For Δ a countable ordinal ≥ 2, Δℝ with its smallest element deleted, is 2-homogeneous.
Elementary epimorphisms
Authors: Rothmaler Philipp 
Published: July 2005

AbstractThe concept ofelementary epimorphismis introduced. Inverse systems of such maps are considered, and a dual of the elementary chain lemma is found (Cor. 4.2). The same is done forpure epimorphisms(Cor. 4.3 and 4.4). Finally, this is applied to certain inverse limits of flat modules (Thm. 6.4) and certain inverse limits of absolutely pure modules (Cor. 6.3).
Dimension theory and parameterized normalization for D-semianalytic sets over non-Archimedean fields
Authors: Çelikler Y. Firat 
Published: July 2005

AbstractWe develop a dimension theory for D-semianalytic sets over an arbitrary non-Arehimedean eomplete field. Our main results are the equivalence of several notions of dimension and a theorem on additivity of dimensions of projections and fibers in characteristic 0. We also prove a parameterized version of normalization for D-semianalytic sets.
Bias, Overview
Authors: Choi Bernard C. K. , Pak Anita W. P. 
Published: July 2005

Abstract
This article provides an overview on bias. Bias is defined as the deviation of results or inferences from the truth, or processes leading to such deviation. The article also provides a catalogue of 109 biases at the following stages of research: literature review 4, study design 31, study execution 3, data collection 46, analysis 15, interpretation of results 7, and publication 3.
Biostatistics, Overview
Authors: Brown W. Byron 
Published: July 2005

Abstract
Biostatistics is concerned with the development and use of statistical methods to solve problems and to answer questions that arise in human biology and medicine. Its development is traced through early work in vital and health statistics, and in heredity, with the important influence of R.A. Fisher on experimental design and statistical inference. Applications in clinical trials, epidemiology, psychometrics, and health services research are described. Current challenges include the impact of computers, Bayesian methods, the use of data banks, longitudinal studies, and research on the human genome. The organization of biostatistics as a professional discipline is discussed.
Risk Assessment for Environmental Chemicals
Authors: Burmaster David E. , Willson Jeanne C. 
Published: July 2005

Abstract
Probabilistic methods are increasingly used in risk assessment, to represent uncertainty and known variability in factors such as exposure and toxicity. Risk assessment follows a five‐step process involving hazard identification, dose‐response assessment (with the development of reference doses and cancer slope factors), exposure assessment (with consideration of exposure pathways and dose estimation), risk characterization, and the analysis of variability and uncertainty. The distinction between assessment and management is discussed.
Statistics, Overview
Authors: Cox D. R. 
Published: July 2005

AbstractThe current topic may be called “statistical science”, encompassing statistical theory and its applications in science and technology. One pillar is probability theory, underpinning statistical inference and forming the basis for special models. Various types of models are distinguished. A second pillar is the design, analysis and interpretation of investigations. The discussion here touches on measurement issues, methods of analysis, detailed techniques, causation, and decision analysis. Formal theories of inference are discussed. Issues arising in the provision and use of official statistics are briefly discussed.
Benefit/Risk Assessment in Prevention Trials
Authors: Costantino Joseph P. 
Published: July 2005

AbstractBenefit/risk assessment (B/RA) is a mathematical procedure to estimate the probability of detrimental outcomes, beneficial outcomes and the net‐effect anticipated from exposure to a given agent or procedure. B/RAs of health‐related outcomes are used for public health planning, decision‐making regarding health care financing, and therapeutic decision‐making in clinical practice. Information obtained from B/RAs based on findings from controlled clinical trials, particularly those with double‐masking of treatment, are most informative for health care planning and decision making because such information is less likely to be bias than is information obtained from observational studies. Thus, B/RAs in prevention trials are an excellent source of information to use as the basis for health care planning and decision‐making. Applications of R/BA in prevention trials are performed as supplements for planning, monitoring and analyzing the trial. These applications can be categorized into three types of assessments. This article provides a description of the three types of assessment performed in prevention trials, defines the statistical algorithms used for each type of assessment and discusses several key methodological and practical issues involve with the application of B/RA to health‐related outcomes.
Data and Safety Monitoring
Authors: O'Brien Peter C. 
Published: July 2005

AbstractWe consider the role of a Data and Safety Monitoring Board (DSMB) in overseeing the conduct of a randomized clinical trial. This includes insuring both the scientific integrity of the study and patient safety, monitoring the occurrence of adverse events and assessing efficacy. Formal stopping rules are particularly useful in clinical trials for monitoring efficacy, with a view towards terminating the trial early if the evidence for or against efficacy becomes overwhelming prior to the scheduled completion of the trial. The most commonly used approaches in formal stopping rules are discussed in some detail. These include the Pocock and O'Brien–Fleming boundaries and the spending function approach developed by Lan and DeMets. Discussion of stochastic curtailment, point and interval estimation associated with early termination, multiple endpoints, and a brief overview of decision theoretic methods (including Bayesian methods) is provided.
Data Monitoring Committees
Authors: Demets David L. 
Published: July 2005

Abstract
Randomized clinical trials are the standard by which new interventions are evaluated for benefit or harm. Federal guidelines in the United States now recommend that all trials have a monitoring plan for early evidence of harm. For trials that have serious irreversible outcomes such as death, heart attack, stroke, or cancer recurrence, an external independent committee called a Data Monitoring Committee (DMCs) is recommended to evaluate the accumulating interim data. Trials for which interim data are convincing for benefit or harm may be terminated early. DMCs began in the early 1970s by trials sponsored by the National Institutes of Health and more recently by the pharmaceutical industry. DMCs review not only the primary outcome data and the serious adverse events but also the recruitment progress, patient compliance to the intervention, other secondary outcome variables, and high risk subgroups of patients if such exist. Because of the complexity of such monitoring, DMCs have a composition with biological, clinical, and biostatistical expertise.
Eligibility and Exclusion Criteria
Authors: Foulkes Mary A. 
Published: July 2005

AbstractDesign characteristics of a clinical trial, such as eligibility and exclusion criteria, are broadly influential in the conduct, interpretation, and impact of trials. The research objectives, the intended inference or generalization of results, the balance of factors affecting the trial recruitment and conduct, all impact the determination of eligibility and exclusion criteria. Clinical contraindications, regulatory and ethical considerations also relate to this determination.
Medical Devices
Authors: Campbell Gregory , Irony Telba Z. , Lao Chang S. , Li Heng , Pennello Gene , Vishnuvajjala R. Lakshmi , Yue Lilly Q. 
Published: July 2005

AbstractA medical device is any item that treats or diagnoses a health condition but whose action is primarily not chemical or biological. The main focus concerns the evaluation of clinical studies to establish the safety and effectiveness of different kinds of medical devices. The design and analysis of medical device studies pose unique statistical challenges. Both nondiagnostic and diagnostic devices are considered. Nondiagnostic devices include therapeutic ones and implants, among others. Statistical issues for these kinds of devices include the placebo effect, sham controls, inability to perform blinded studies, noninferiority, survival analysis, repeated measures, and historical controls. Diagnostic devices pose a very diverse set of challenges, with markedly different design and analysis considerations. Special attention is devoted here to microarrays in particular. Bayesian approaches to medical device studies are discussed.
Missing Data in Clinical Trials
Authors: Murray Gordon D. 
Published: July 2005

AbstractMissing data is an almost universal problem in clinical trials, and substantial bias can arise if the statistical analysis does not take proper account of the issue. The article reviews the different mechanisms that can lead to missing data, and describes appropriate approaches to the statistical analysis. As in so many aspects of clinical trials, the correct approach depends crucially on what question is being asked, and, in particular, whether the trial design is explanatory or pragmatic.
Multicenter Trials
Authors: Bryant John , Cronin Walter , Wieand Sam 
Published: July 2005

Abstract
The chapter deals with multicenter clinical trials, which are defined as studies involving two or more field sites conducted according to a common protocol that uses a single data coordinating center to receive, process, and analyze study data. Several examples are provided. Organizational, structural, and analytic aspects of trials, and guidelines for the conduct of such studies are discussed.
Quality of Life
Authors: Fairclough Diane L. , Ganz Patricia A. 
Published: July 2005

AbstractIn the health sciences, assessment of quality of life and other patient‐reported outcomes are now an integral component of patient‐focused research. Health‐related quality of life (HRQoL) is a multidimensional construct that assesses the extent to which one's usual or expected physical, emotional, and social well‐being are impacted by a medical condition or its treatment. HRQoL may be assessed using generic or disease‐specific instruments. These instruments consist of a set of questions, method of administration, instructions for administration, method of scoring and analysis, and interpretation. Validation of these instruments includes assessment of content validity, internal consistency, test–retest reliability, and discriminant and predictive validity. Some of the statistical issues that arise in the analysis of studies with HRQoL assessments are multiple endpoints, missing data (informative dropout), and interpretation (statistical versus clinical significance).
Sample Size Determination for Clinical Trials
Authors: Lakatos E. 
Published: July 2005

AbstractConceptual issues in sample size calculation for clinical trials are discussed. Each parameter and related issues are highlighted: type I and II errors and the balance between them, one versus two‐sided testing, the smallest clinically meaningful difference versus the anticipated treatment effect, endpoint selection, multiple comparisons, missing data, unequal allocation, repeated measures, equivalence, and group sequential trials. For survival trials, conceptual issues are discussed in further detail, including the binomial versus log rank statistic, exponential versus proportional and nonproportional hazards, and adjustment for treatment lag, staggered entry, noncompliance, drop‐in, loss‐to‐follow‐up and competing risks, and duration of treatment effect.
Textbooks in Clinical Trials
Authors: Massaro Joseph M. 
Published: July 2005

Abstract
In general, whether you are a student, clinical trials professional, or an instructor, choosing references or course textbooks can be overwhelming, even after deciding upon a specific learning objective. In this article, we hope to offer guidance on appropriate textbooks or references to those interested in (a) an introduction or overview of the design and components of clinical trials; and (b) statistical analysis of clinical trial data. What follows is not a critical review of texts, since the number of texts is too numerous for such a handling here. Rather, what follows is a brief description of various texts discussing clinical trials and the audience for which the text is meant. Also presented is this author's judgment on whether each text might be more useful as a textbook or a reference for a clinical trial statistics course or for a clinical trial introduction/overview/design course. Note that, again, this article focuses on various texts giving an introduction or overview of clinical trials, and on those texts focusing on analysis. The numerous other texts focusing on issues such as regulatory aspects or data management, or focusing on clinical trials in certain indications are not included here.
Women's Health Initiative: Statistical Aspects and Selected Early Results
Authors: Prentice Ross L. , Anderson Garnet L. 
Published: July 2005

Abstract
An overview is provided of the women's health initiative clinical trial and observational study of 161 808 postmenopausal women in the age range 50 to 79. The clinical trial includes 68 132 women in a partial factorial design having four intervention comparisons: a low‐fat eating pattern among 48 835 women; a hormone therapy trial of 0.625 mg per day of conjugated equine estrogen among 10 739 women who were posthysterectomy at baseline; a hormone therapy trial of this same estrogen plus 2.5 mg per day of medroxyprogesterone acetate among 16 608 women with uterus at baseline; and a calcium (1000 mg/day) plus vitamin D (400 international units/day) trial among 36 282 women. Each CT component had its specified primary and secondary hypotheses, along with an overriding emphasis on overall health benefits versus risks. A so‐called global index was defined for each CT component as the earliest occurrence of a set of clinical outcomes plausibly affected by the intervention, or death from other causes. Specialized data management communication, quality assurance, and data monitoring procedures were established to support this large and complex research program. Some detail is provided on the results of the combined hormone trial component, which was stopped early in 2002 when the external Data and Safety Monitoring Board judged that overall health risks exceeded benefits over an average follow‐up period in excess of five years.
Gestational Age
Authors: Macfarlane Alison 
Published: July 2005

Abstract
The World Health Organization defines the duration of a pregnancy as the time since the first day of the last normal menstrual period. This can be problematic if women conceive soon after stopping oral contraception or have irregular periods; so ultrasound estimates are increasingly used in countries where it is in common use. The World Health Organization also subdivides gestational ages into preterm, term and postterm.
Nutritional Exposure Measures
Authors: Bingham S. 
Published: July 2005

Abstract
In all methods of measurement of nutritional exposure, some estimate of the weight of food consumed is required, and for the determination of nutrient or other food component intake, either an appropriate description for use with food tables is needed or a portion must be available for chemical analysis. Different methods are available to assess the weight of food, and they vary in accuracy, complexity, and cost. All methods have different types of error structure, so that the magnitude of the error varies according to the method and may not be predictable. Validation studies of less accurate methods may be conducted to assess accuracy but regression dilution may be considerably underestimated due to error correlation between the reference and test methods. In case control studies, estimates of past dietary consumption are closely related to present consumption, and the discrepancy between actual and recalled past diet is greater the longer the period of recall attempted. All methods may be subject to systematic bias from under‐ or overreporting.
Occupational Mortality
Authors: Lynge Elsebeth 
Published: July 2005

Abstract
The study of occupational mortality involves the systematic tabulation of mortality by occupational or socio‐economic group. Three main methods are used to conduct these studies: cross‐sectional studies, death certificate studies, and follow‐up studies. Cross‐sectional studies were undertaken in England and Wales from 1851 to 1979–1983, and these studies have provided key data on social inequalities in health. Death certificate studies have been used for identification of occupational groups with high excess risks from specific diseases. Follow‐up studies require linkage of individual records, typically from censuses and death certificates. They have been undertaken in, for example, all the Nordic countries. The follow‐up studies have shown a high mortality for all marginal groups of the labor market, a social gradient in overall mortality, low mortality among farmers, and a widening gap between the mortality rates of blue and white collar workers.