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::Repeated cross-sectional samples are common in national surveys of health like the National Health Interview Survey (NHIS). Because population health outcomes generally evolve slowly, pooling data across years can improve the precision of current-year annual estimates of disease prevalence and other health outcomes. P...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3897
更新日期:2011-02-28 00:00:00
abstract::Health surveillance involves collecting public health data on chronic and infectious diseases to detect changes in disease incidence rates in order to improve public health. Timely detection of disease clusters is essential in prospective public health surveillance. Most existing health surveillance research is based ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3877
更新日期:2011-02-28 00:00:00
abstract::Multiple imputation by chained equations is a flexible and practical approach to handling missing data. We describe the principles of the method and show how to impute categorical and quantitative variables, including skewed variables. We give guidance on how to specify the imputation model and how many imputations ar...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4067
更新日期:2011-02-20 00:00:00
abstract::Three-arm trials including the experimental treatment, an active reference treatment and a placebo are recommended in the guidelines of the ICH and EMEA/CPMP as a useful approach to the assessment of assay sensitivity. Generally, the acceptable non-inferiority margin Δ has been defined as the maximum clinically irrele...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4099
更新日期:2011-02-10 00:00:00
abstract::Standard approaches to analysis of randomized controlled trials (RCTs) using Markov models make it difficult to generalize treatment effects to new patient groups and synthesize evidence across trials. This paper demonstrates how pair-wise and mixed treatment comparison meta-analysis can be applied to event history da...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4059
更新日期:2011-01-30 00:00:00
abstract::Appropriate quantification of added usefulness offered by new markers included in risk prediction algorithms is a problem of active research and debate. Standard methods, including statistical significance and c statistic are useful but not sufficient. Net reclassification improvement (NRI) offers a simple intuitive w...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4085
更新日期:2011-01-15 00:00:00
abstract::Frailty models are encountered in many medical applications, yet little research has been devoted to develop measures that quantify the predictive ability of these models. In this paper, we elaborate on the concept of the concordance probability to clustered data, resulting in an 'Overall Conditional C-index' or bfC(O...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4058
更新日期:2010-12-30 00:00:00
abstract::We have developed a method to longitudinally classify subjects into two or more prognostic groups using longitudinally observed values of markers related to the prognosis. We assume the availability of a training data set where the subjects' allocation into the prognostic group is known. The proposed method proceeds i...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3849
更新日期:2010-12-30 00:00:00
abstract::Methodology for the meta-analysis of individual patient data with survival end-points is proposed. Motivated by questions about the reliance on hazard ratios as summary measures of treatment effects, a parametric approach is considered and percentile ratios are introduced as an alternative to hazard ratios. The genera...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4086
更新日期:2010-12-20 00:00:00
abstract::Interval-censored data are commonly found in studies of diseases that progress without symptoms, which require clinical evaluation for detection. Several techniques have been suggested with independent assumption. However, the assumption will not be valid if observations come from clusters. Furthermore, when the clust...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4042
更新日期:2010-12-10 00:00:00
abstract::We consider using observational data to estimate the effect of a treatment on disease recurrence, when the decision to initiate treatment is based on longitudinal factors associated with the risk of recurrence. The effect of salvage androgen deprivation therapy (SADT) on the risk of recurrence of prostate cancer is in...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4017
更新日期:2010-11-10 00:00:00
abstract::The case-control study is a simple and an useful method to characterize the effect of a gene, the effect of an exposure, as well as the interaction between the two. The control-free case-only study is yet an even simpler design, if interest is centered on gene-environment interaction only. It requires the sometimes pl...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4028
更新日期:2010-10-30 00:00:00
abstract::Patient reported outcome and observer evaluative studies in clinical trials and post-hoc analyses often use instruments that measure responses on ordinal-rating or Likert scales. We propose a flexible distributional approach by modeling the change scores from the baseline to the end of the study using independent beta...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4012
更新日期:2010-10-30 00:00:00
abstract::In applications such as medical statistics and genetics, we encounter situations where a large number of highly correlated predictors explain a response. For example, the response may be a disease indicator and the predictors may be treatment indicators or single nucleotide polymorphisms (SNPs). Constructing a good pr...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4014
更新日期:2010-10-30 00:00:00
abstract::In the field of cluster detection, a weighted normal model-based scan statistic was recently developed to analyze regional continuous data and to evaluate the clustering pattern of pre-defined cells (such as state, county, tract, school, hospital) that include many individuals. The continuous measures of interest are,...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3990
更新日期:2010-10-15 00:00:00
abstract::Maps of estimated disease rates over multiple time periods are useful tools for gaining etiologic insights regarding potential exposures associated with specific locations and times. In this paper, we describe an extension of the Gangnon-Clayton model for spatial clustering to spatio-temporal data. As in the purely sp...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3984
更新日期:2010-09-30 00:00:00
abstract::In this paper, we consider pooling schemes in which samples are to be tested in two-stages. We show that when batch size is limited as well as pool size, selection schemes tend to be more efficient and flexible. Formulae for the efficiencies of square arrays in all dimensions and for all selection schemes are given in...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3965
更新日期:2010-09-20 00:00:00
abstract::In behavioral, biomedical, and social-psychological sciences, it is common to encounter latent variables and heterogeneous data. Mixture structural equation models (SEMs) are very useful methods to analyze these kinds of data. Moreover, the presence of missing data, including both missing responses and missing covaria...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3915
更新日期:2010-08-15 00:00:00
abstract::In repeated measures settings, modeling the correlation pattern of the data can be immensely important for proper analyses. Accurate inference requires proper choice of the correlation model. Optimal efficiency of the estimation procedure demands a parsimonious parameterization of the correlation structure, with suffi...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3928
更新日期:2010-07-30 00:00:00
abstract::There is considerable public concern about health disparities among different cultural/racial/ethnic groups. Important process measures that might reflect inequities are treated prevalence and the service utilization rate in a defined period of time. We have previously described a method for estimating N, the distinct...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3904
更新日期:2010-07-20 00:00:00
abstract::Performance of a diagnostic test is ideally evaluated by a comparison of the test results to a gold standard for all the patients in a study. In practice, however, it is common for a subset of study patients to have the gold standard not verified (missing) due to ethical or expense considerations. Sensitivity and spec...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3899
更新日期:2010-07-10 00:00:00
abstract::When a cancer patient develops a new tumor it is necessary to determine if it is a recurrence (metastasis) of the original cancer, or an entirely new occurrence of the disease. This is accomplished by assessing the histo-pathology of the lesions. However, there are many clinical scenarios in which this pathological di...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3866
更新日期:2010-07-10 00:00:00
abstract::The National Children's Study is a national household probability sample designed to identify 100,000 children at birth and follow the sampled children for 21 years. Data from the study will support examining numerous hypotheses concerning genetic and environmental effects on the health and development of children. Th...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3891
更新日期:2010-06-15 00:00:00
abstract::Genetic markers can be used as instrumental variables, in an analogous way to randomization in a clinical trial, to estimate the causal relationship between a phenotype and an outcome variable. Our purpose is to extend the existing methods for such Mendelian randomization studies to the context of multiple genetic mar...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3843
更新日期:2010-05-30 00:00:00
abstract::For bivariate meta-analysis of diagnostic studies, likelihood approaches are very popular. However, they often run into numerical problems with possible non-convergence. In addition, the construction of confidence intervals is controversial. Bayesian methods based on Markov chain Monte Carlo (MCMC) sampling could be u...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3858
更新日期:2010-05-30 00:00:00
abstract::Age-period-cohort (APC) analysis is widely used in cancer epidemiology to model trends in cancer rates. We develop methods for comparative APC analysis of two independent cause-specific hazard rates assuming that an APC model holds for each one. We construct linear hypothesis tests to determine whether the two hazards...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3865
更新日期:2010-05-20 00:00:00
abstract::Novel therapies are challenging the standards of drug development. Agents with specific biologic targets, unknown dose-efficacy curves, and limited toxicity mandate novel designs to identify biologically optimal doses. We review two model-based designs that utilize either a proportional odds model or a continuation ra...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3706
更新日期:2010-05-10 00:00:00
abstract::In medical research, risk difference (RD) and number needed to treat (NNT) measures for survival times have been mainly proposed without consideration of covariates. In this paper, we develop adjusted RD and NNT measures for use in observational studies with survival time outcomes within the framework of the Cox propo...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3793
更新日期:2010-03-30 00:00:00
abstract::Studies based on aggregated hospital outcome data have established that there is a relationship between nurse staffing and adverse events. However, this result could not be confirmed in Belgium where 96 per cent of the variability of nurse staffing levels over nursing units (belonging to different hospitals) is explai...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3756
更新日期:2010-03-30 00:00:00
abstract::In many chronic disease processes subjects are at risk of two or more types of events. We describe a bivariate mixed Poisson model in which a copula function is used to model the association between two gamma distributed random effects. The resulting model is a bivariate negative binomial process in which each type of...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3830
更新日期:2010-03-15 00:00:00
abstract::Machine learning techniques such as classification and regression trees (CART) have been suggested as promising alternatives to logistic regression for the estimation of propensity scores. The authors examined the performance of various CART-based propensity score models using simulated data. Hypothetical studies of v...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3782
更新日期:2010-02-10 00:00:00
abstract::We estimate a Cox proportional hazards model where one of the covariates measures the level of a subject's cognitive functioning by grading the total score obtained by the subject on the items of a questionnaire. A case study is presented where the sample includes partial respondents, who did not answer some questionn...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3773
更新日期:2010-01-30 00:00:00
abstract::This paper considers the analysis of longitudinal data complicated by the fact that during follow-up patients can be in different disease states, such as remission, relapse or death. If both the response of interest (for example, quality of life (QOL)) and the amount of missing data depend on this disease state, ignor...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3755
更新日期:2009-12-30 00:00:00
abstract::This paper discusses regression analysis of multivariate current status failure time data (The Statistical Analysis of Interval-censoring Failure Time Data. Springer: New York, 2006), which occur quite often in, for example, tumorigenicity experiments and epidemiologic investigations of the natural history of a diseas...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3715
更新日期:2009-11-30 00:00:00
abstract::In observational cohort studies we may wish to examine the associations between fixed patient characteristics and the longitudinal changes from baseline in a repeated outcome measure. Many biological and other outcome measures are known to be subject to measurement error and biological variation. In an initial analysi...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3725
更新日期:2009-11-20 00:00:00
abstract::We develop reinforcement learning trials for discovering individualized treatment regimens for life-threatening diseases such as cancer. A temporal-difference learning method called Q-learning is utilized that involves learning an optimal policy from a single training set of finite longitudinal patient trajectories. A...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3720
更新日期:2009-11-20 00:00:00
abstract::Biostatisticians have frequently uncritically accepted the measurements provided by their medical colleagues engaged in clinical research. Such measures often involve considerable loss of information. Particularly, unfortunate is the widespread use of the so-called 'responder analysis', which may involve not only a lo...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3603
更新日期:2009-11-20 00:00:00
abstract::Many different methods have been proposed for the analysis of cluster randomized trials (CRTs) over the last 30 years. However, the evaluation of methods on overdispersed count data has been based mostly on the comparison of results using empiric data; i.e. when the true model parameters are not known. In this study, ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3681
更新日期:2009-10-30 00:00:00
abstract::In a variety of biomedical applications, particularly those involving screening for infectious diseases, testing individuals (e.g. blood/urine samples, etc.) in pools has become a standard method of data collection. This experimental design, known as group testing (or pooled testing), can provide a large reduction in ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3678
更新日期:2009-10-15 00:00:00
abstract::Matched-pair designs have been commonly employed in diagnostic, epidemiologic and laboratory studies. For estimation of a ratio of two marginal probabilities in matched-pair data, a Wald-type logarithmic method is computationally simple, but an actual coverage rate is known to be smaller than a nominal one and a lengt...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3685
更新日期:2009-10-15 00:00:00