解剖学和形态学
麻醉学
听力与言语-语言病理学
行为科学
心脏和心血管系统
细胞和组织工程学
临床神经病学
危重症监护医学
牙科,口腔外科和医学
皮肤病学
急诊医学
内分泌学和新陈代谢
肠胃学和肝脏学
老人病学和老年医学
卫生保健科学和服务
血液学
免疫学
传染病
综合和补充性医学
医学伦理学
医学信息学
医学实验室技术
医学,全科和内科
医学,法律
医学,研究和试验
神经系统科学
护理
营养学和饮食学
产科医学和妇科医学
肿瘤学
眼科学
整形外科学
耳鼻喉科学
病理学
儿科学
周围血管疾病
药理学和药剂学
生理学
基本医疗保健
精神病学
公共、环境和职业卫生
放射学,核医学和医学成像
康复学
生殖生物学
呼吸系统
风湿病学
运动科学
外科学
毒理学
热带医学
泌尿学和肾脏学
病毒学
老年医学
健康政策和服务
心理学,临床
abstract::The effective dose (ED) is the pharmaceutical dosage required to produce a therapeutic response in a fixed proportion of the patients. When only one drug is considered, the problem is a univariate one and has been well-studied. However, in the multidimensional setting, that is, in the presence of combinations of agent...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6226
更新日期:2014-10-30 00:00:00
abstract::Delay in the outcome variable is challenging for outcome-adaptive randomization, as it creates a lag between the number of subjects accrued and the information known at the time of the analysis. Motivated by a real-life pediatric ulcerative colitis trial, we consider a case where a short-term predictor is available fo...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6222
更新日期:2014-10-15 00:00:00
abstract::Multilevel mixed effects survival models are used in the analysis of clustered survival data, such as repeated events, multicenter clinical trials, and individual participant data (IPD) meta-analyses, to investigate heterogeneity in baseline risk and covariate effects. In this paper, we extend parametric frailty model...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6191
更新日期:2014-09-28 00:00:00
abstract::Funnel plots are widely used to visualize grouped data, for example, in institutional comparison. This paper extends the concept to a multi-level setting, displaying one level at a time, adjusted for the other levels, as well as for covariates at all levels. These level-adjusted funnel plots are based on a Markov chai...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5677
更新日期:2014-09-20 00:00:00
abstract::Clinical trials utilizing predictive biomarkers have become a research focus in personalized medicine. We investigate the effects of biomarker misclassification on the design and analysis of stratified biomarker clinical trials. For a variety of inference problems including marker-treatment interaction in particular, ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6164
更新日期:2014-08-15 00:00:00
abstract::The present study investigates the performance of several statistical tests to detect publication bias in diagnostic meta-analysis by means of simulation. While bivariate models should be used to pool data from primary studies in diagnostic meta-analysis, univariate measures of diagnostic accuracy are preferable for t...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6177
更新日期:2014-08-15 00:00:00
abstract::Writing the variance of the Mantel-Haenszel estimator under the null of homogeneity and inverting the corresponding test, we arrive at an improved confidence interval for the common risk difference in stratified 2 × 2 tables. This interval outperforms a variety of other intervals currently recommended in the literatur...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6122
更新日期:2014-07-30 00:00:00
abstract::With the increasing availability of detailed clinical information, there is optimism that treatment choices can be selectively directed to those individuals most likely to benefit. While standard clinical trials can establish whether a treatment appears to be effective on average, subsequent work is needed to determin...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6138
更新日期:2014-07-30 00:00:00
abstract::Testing involving the intra-class kappa coefficient is commonly performed in order to assess agreement involving categorical ratings. A number of procedures have been proposed, which make use of the limiting null distribution as the sample size goes to infinity in order to compute the observed significance. As with ma...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6135
更新日期:2014-07-30 00:00:00
abstract::Recently, there has been much work on early phase cancer designs that incorporate both toxicity and efficacy data, called phase I-II designs because they combine elements of both phases. However, they do not explicitly address the phase II hypothesis test of H0 : p ≤ p0 , where p is the probability of efficacy at the ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6124
更新日期:2014-07-20 00:00:00
abstract::It is unclear to what extent the incremental predictive performance of a novel biomarker is impacted by the method used to control for standard predictors. We investigated whether adding a biomarker to a model with a published risk score overestimates its incremental performance as compared to adding it to a multivari...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6165
更新日期:2014-07-10 00:00:00
abstract::Clinical trials often assess efficacy by comparing treatments on the basis of two or more event-time outcomes. In the case of cancer clinical trials, progression-free survival (PFS), which is the minimum of the time from randomization to progression or to death, summarizes the comparison of treatments on the hazards f...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6096
更新日期:2014-05-30 00:00:00
abstract::Risk prediction models play an important role in prevention and treatment of several diseases. Models that are in clinical use are often refined and improved. In many instances, the most efficient way to improve a successful model is to identify subgroups for which there is a specific biological rationale for improvem...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6077
更新日期:2014-05-20 00:00:00
abstract::In cancer clinical trials, patients often experience a recurrence of disease prior to the outcome of interest, overall survival. Additionally, for many cancers, there is a cured fraction of the population who will never experience a recurrence. There is often interest in how different covariates affect the probability...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6056
更新日期:2014-05-10 00:00:00
abstract::In vitro fertilization (IVF) is an increasingly common method of assisted reproductive technology. Because of the careful observation and follow-up required as part of the procedure, IVF studies provide an ideal opportunity to identify and assess clinical and demographic factors along with environmental exposures that...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6050
更新日期:2014-05-10 00:00:00
abstract::Treatment effects for multiple outcomes can be meta-analyzed separately or jointly, but no systematic empirical comparison of the two approaches exists. From the Cochrane Library of Systematic Reviews, we identified 45 reviews, including 1473 trials and 258,675 patients, that contained two or three univariate meta-ana...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6044
更新日期:2014-04-30 00:00:00
abstract::Huntington's disease (HD) is a neurodegenerative disorder with a dominant genetic mode of inheritance caused by an expansion of CAG repeats on chromosome 4. Typically, a longer sequence of CAG repeat length is associated with increased risk of experiencing earlier onset of HD. Previous studies of the association betwe...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5971
更新日期:2014-04-15 00:00:00
abstract::Competing compartment models of different complexities have been used for the quantitative analysis of dynamic contrast-enhanced magnetic resonance imaging data. We present a spatial elastic net approach that allows to estimate the number of compartments for each voxel such that the model complexity is not fixed a pri...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5997
更新日期:2014-03-15 00:00:00
abstract::Methods for multiple informants help to estimate the marginal effect of each multiple source predictor and formally compare the strength of their association with an outcome. We extend multiple informant methods to the case of hierarchical data structures to account for within cluster correlation. We apply the propose...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5967
更新日期:2014-02-20 00:00:00
abstract::Health questionnaires are often built up from sets of questions that are totaled to obtain a sum score. An important consideration in designing questionnaires is to minimize respondent burden. An increasingly popular method for efficient measurement is computerized adaptive testing; unfortunately, many health question...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5936
更新日期:2014-02-10 00:00:00
abstract::For patients who were previously treated for prostate cancer, salvage hormone therapy is frequently given when the longitudinal marker prostate-specific antigen begins to rise during follow-up. Because the treatment is given by indication, estimating the effect of the hormone therapy is challenging. In a previous pape...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5890
更新日期:2014-01-30 00:00:00
abstract::Antimicrobial resistance has become one of the main public health burdens of the last decades, and monitoring the development and spread of non-wild-type isolates has therefore gained increased interest. Monitoring is performed based on the minimum inhibitory concentration (MIC) values, which are collected through the...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5939
更新日期:2014-01-30 00:00:00
abstract::We consider the use of the assurance method in clinical trial planning. In the assurance method, which is an alternative to a power calculation, we calculate the probability of a clinical trial resulting in a successful outcome, via eliciting a prior probability distribution about the relevant treatment effect. This i...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5916
更新日期:2014-01-15 00:00:00
abstract::We study the competing risks model and show that the cause j cumulative incidence function integrated from 0 to τ has a natural interpretation as the expected number of life years lost due to cause j before time τ. This is analogous to the τ-restricted mean lifetime, which is the survival function integrated from 0 to...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5903
更新日期:2013-12-30 00:00:00
abstract::A method for detecting deviations from the Loewe additive drug combination reference model for in vitro drug combination experimentation is described. It is often difficult to fit a response surface model to drug combination data, especially in situations where the experimental design contains a sparse set of combinat...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5905
更新日期:2013-12-20 00:00:00
abstract::Correlated data are obtained in longitudinal epidemiological studies, where repeated measurements are taken on individuals or groups over time. Such longitudinal data are ideally analyzed using multilevel modeling approaches, which appropriately account for the correlations in repeated responses in the same individual...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5880
更新日期:2013-12-10 00:00:00
abstract::We describe rank-based approaches to assess principal stratification treatment effects in studies where the outcome of interest is only well-defined in a subgroup selected after randomization. Our methods are sensitivity analyses, in that estimands are identified by fixing a parameter and then we investigate the sensi...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5849
更新日期:2013-11-20 00:00:00
abstract::Motivated by a study about prompt coronary angiography in myocardial infarction, we propose a method to estimate the causal effect of a treatment in two-arm experimental studies with possible noncompliance in both treatment and control arms. We base the method on a causal model for repeated binary outcomes (before and...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5856
更新日期:2013-11-10 00:00:00
abstract::In conventional survival analysis there is an underlying assumption that all study subjects are susceptible to the event. In general, this assumption does not adequately hold when investigating the time to an event other than death. Owing to genetic and/or environmental etiology, study subjects may not be susceptible ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5845
更新日期:2013-10-30 00:00:00
abstract::This paper concerns using modified weighted Schoenfeld residuals to test the proportionality of subdistribution hazards for the Fine-Gray model, similar to the tests proposed by Grambsch and Therneau for independently censored data. We develop a score test for the time-varying coefficients based on the modified Schoen...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5815
更新日期:2013-09-30 00:00:00
abstract::To study the effect of a mega hydropower dam in southwest Ethiopia on malaria incidence, we have set up a longitudinal study. To gain insight in temporal and spatial aspects, that is, in time (period = year-season combination) and location (village), we need models that account for these effects. The frailty model w...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5752
更新日期:2013-08-15 00:00:00
abstract::Random forest is a supervised learning method that combines many classification or regression trees for prediction. Here we describe an extension of the random forest method for building event risk prediction models in survival analysis with competing risks. In case of right-censored data, the event status at the pred...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5775
更新日期:2013-08-15 00:00:00
abstract::We construct nonparametric regression estimators of a number of temporal functions in a multistate system based on a continuous univariate baseline covariate. These estimators include state occupation probabilities, state entry, exit, and waiting (sojourn) time distribution functions of a general progressive (e.g., ac...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5703
更新日期:2013-07-30 00:00:00
abstract::The statistical analysis of panel count data has recently attracted a great deal of attention, and a number of approaches have been developed. However, most of these approaches are for situations where the observation and follow-up processes are independent of the underlying recurrent event process unconditional or co...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5724
更新日期:2013-07-30 00:00:00
abstract::Estimates of relative efficacy between alternative treatments are crucial for decision making in health care. Bayesian mixed treatment comparison models provide a powerful methodology to obtain such estimates when head-to-head evidence is not available or insufficient. In recent years, this methodology has become wide...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5764
更新日期:2013-07-30 00:00:00
abstract::In noninferiority studies, a limit of indifference is used to express a tolerance in results such that the clinician would regard such results as being acceptable or 'not worse'. We applied this concept to a measure of accuracy, the Receiver Operating Characteristic (ROC) curve, for a sequence of tests. We expressed a...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5741
更新日期:2013-07-20 00:00:00
abstract::Timeliness of a public health surveillance system is one of its most important characteristics. The process of predicting the present situation using available incomplete information from surveillance systems has received the term nowcasting and has high public health interest. Generally in Europe, general practitione...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5670
更新日期:2013-07-10 00:00:00
abstract::Cross-sectional designs are often used to monitor the proportion of infections and other post-surgical complications acquired in hospitals. However, conventional methods for estimating incidence proportions when applied to cross-sectional data may provide estimators that are highly biased, as cross-sectional designs t...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5608
更新日期:2013-06-30 00:00:00
abstract::Methods for dealing with tied event times in the Cox proportional hazards model are well developed. Also, the partial likelihood provides a natural way to handle covariates that change over time. However, ties between event times and the times that discrete time-varying covariates change have not been systematically s...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5683
更新日期:2013-06-30 00:00:00
abstract::Risk prediction procedures can be quite useful for the patient's treatment selection, prevention strategy, or disease management in evidence-based medicine. Often, potentially important new predictors are available in addition to the conventional markers. The question is how to quantify the improvement from the new ma...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5647
更新日期:2013-06-30 00:00:00