Abstract:
:Box-Cox transformation is investigated for regression models for left-censored data. Examples are provided using coronary calcification data from the Multi-Ethnic Study of Atherosclerosis and pharmacokinetic data of a nicotine nasal spray.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Han C,Kronmal Rdoi
10.1002/sim.1925subject
Has Abstractpub_date
2004-12-15 00:00:00pages
3671-9issue
23eissn
0277-6715issn
1097-0258journal_volume
23pub_type
杂志文章abstract::Teaching statistics to medical students is a challenging and often unrewarding task. However, few would argue the need for statistics in the medical school curriculum. In recent years, there has been a growing call for teaching only statistical concepts in medical schools. We strongly oppose this opinion and offer an ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.2906
更新日期:2007-10-15 00:00:00
abstract::In the comparison of two or more treatment groups to a control group, consider a study with non-decreasing repeated measurements of the same characteristic taken over a common set of time points for each subject. Based on the vector of possibly incomplete responses from each subject, this paper considers asymptoticall...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0258(19961215)15:23<2509::AID-S
更新日期:1996-12-15 00:00:00
abstract::Conditional power (CP) is the probability that the final study result will be statistically significant, given the data observed thus far and a specific assumption about the pattern of the data to be observed in the remainder of the study, such as assuming the original design effect, or the effect estimated from the c...
journal_title:Statistics in medicine
pub_type: 杂志文章,评审
doi:10.1002/sim.2151
更新日期:2005-09-30 00:00:00
abstract::Both the variation of positive responses (negative responses) among individuals and the internal correlation among responses for the same individual affect the precision of the estimate of sensitivity (specificity). To estimate the sensitivity (specificity) of a medical diagnostic test, this paper proposes a Bayesian ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780081007
更新日期:1989-10-01 00:00:00
abstract::Unmeasured confounding is a common concern when researchers attempt to estimate a treatment effect using observational data or randomized studies with nonperfect compliance. To address this concern, instrumental variable methods, such as 2-stage predictor substitution (2SPS) and 2-stage residual inclusion (2SRI), have...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.7636
更新日期:2018-05-30 00:00:00
abstract::The EQ-5D, a widely used multiattribute utility instrument, is commonly used in health economic evaluations where the goal is to decide on which treatments to reimburse. Like other instruments, value sets of the EQ-5D are constructed using valuation studies typically valuing a subset of the health states and using pre...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.8592
更新日期:2020-10-15 00:00:00
abstract::Elevated plasma levels of apolipoproteins A1 (apoA1) and B (apoB) are important protective factors and risk factors, respectively, for atherosclerosis and coronary heart disease. It is well known that both apoA1 and apoB reveal strong familial aggregation. Our goal was to investigate whether exogenous variables influe...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/1097-0258(20001230)19:24<3345::aid-sim829>
更新日期:2000-12-30 00:00:00
abstract:BACKGROUND:It has been recommended that onset of antidepressant action be assessed using survival analyses with assessments taken at least twice per week. However, such an assessment schedule is problematic to implement. The present study assessed the feasibility of comparing onset of action between treatments using a ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.2309
更新日期:2006-07-30 00:00:00
abstract::This paper reviews several emerging and recurrent issues relating to the drug development process. These emerging issues include changes to the FDA regulatory environment, internationalization of drug development, advances in computer technology and visualization tools, and efforts to incorporate meta-analysis methodo...
journal_title:Statistics in medicine
pub_type: 杂志文章,评审
doi:10.1002/(sici)1097-0258(19990915/30)18:17/18<2301:
更新日期:1999-09-15 00:00:00
abstract::Vaccination in populations can have several kinds of effects. Establishing that vaccination produces population-level effects beyond the direct effects in the vaccinated individuals can have important consequences for public health policy. Formal methods have been developed for study designs and analysis that can esti...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.7392
更新日期:2018-01-30 00:00:00
abstract::In biomedical studies and clinical trials, repeated measures are often subject to some upper and/or lower limits of detection. Hence, the responses are either left or right censored. A complication arises when more than one series of responses is repeatedly collected on each subject at irregular intervals over a perio...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.8017
更新日期:2019-03-15 00:00:00
abstract::Lung function tests are used both clinically, in assessing disease, and epidemiologically, in identifying those factors which influence the growth and aging process of the lungs. The user must beware of several common pitfalls in the use of these tests, however. First, the commonly used tests of lung function can only...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780070106
更新日期:1988-01-01 00:00:00
abstract::Biomarkers, increasingly used in biomedical studies for the diagnosis and prognosis of acute and chronic diseases, provide insight into the effectiveness of treatments and potential pathways that can be used to guide future treatment targets. The measurement of these markers is often limited by the sensitivity of the ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4503
更新日期:2012-07-30 00:00:00
abstract::We consider several sources of heterogeneity in a clinical trial with patients' survival time as the main response criterion: differences in prognosis which can be attributed to a latent or ignored prognostic factor; differences in treatment efficacy in subgroups of patients, and differences in treatment combinations ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780060708
更新日期:1987-10-01 00:00:00
abstract::We present methods for binomial regression when the outcome is determined using the results of a single diagnostic test with imperfect sensitivity and specificity. We present our model, illustrate it with the analysis of real data, and provide an example of WinBUGS program code for performing such an analysis. Conditi...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.1656
更新日期:2004-04-15 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::The setting of a quarantine time for an emerging infectious disease will depend on current knowledge concerning incubation times. Methods for the analysis of information on incubation times are investigated with a particular focus on inference regarding a possible maximum incubation time, after which an exposed indivi...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.2206
更新日期:2005-11-30 00:00:00
abstract::In the presence of confounding, the consistency assumption required for identification of causal effects may be violated due to misclassification of the outcome variable. We introduce an inverse probability weighted approach to rebalance covariates across treatment groups while mitigating the influence of differential...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.7522
更新日期:2018-02-10 00:00:00
abstract::Many extensions of survival models based on the Cox proportional hazards approach have been proposed to handle clustered or multiple event data. Of particular note are five Cox-based models for recurrent event data: Andersen and Gill (AG); Wei, Lin and Weissfeld (WLW); Prentice, Williams and Peterson, total time (PWP-...
journal_title:Statistics in medicine
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1002/(sici)1097-0258(20000115)19:1<13::aid-sim2
更新日期:2000-01-15 00:00:00
abstract::We propose a new design for dose finding for cytotoxic agents in two ordered groups of patients. By ordered groups, we mean that prior to the study there is clinical information that would indicate that for a given dose one group would be more susceptible to toxicities than patients in the other group. The designs are...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.7133
更新日期:2017-01-30 00:00:00
abstract::We study the group bridge and the adaptive group bridge penalties for competing risks quantile regression with group variables. While the group bridge consistently identifies nonzero group variables, the adaptive group bridge consistently selects variables not only at group level but also at within-group level. We all...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.7619
更新日期:2018-04-30 00:00:00
abstract::Algorithms for identifying public health threats or disease outbreaks are vulnerable to false alarms arising from sudden shifts in health-care utilization or data participation. This paper describes a method of reducing false alerts in automated public health surveillance algorithms, and in particular, automated syndr...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4204
更新日期:2011-06-30 00:00:00
abstract::Comparative calibration is the broad statistical methodology used to assess the calibration of a set of p instruments, each designed to measure the same characteristic, on a common group of individuals. Different from the usual calibration problem, the true underlying quantity measured is unobservable. Many authors ha...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19970830)16:16<1889::aid-s
更新日期:1997-08-30 00:00:00
abstract::For many HIV-infected patients, use of antiretroviral therapy (ART) results in a sustained suppression of plasma viral load to undetectable levels. However, due to lack of antigenic stimulation, this may also result in a gradual loss of cell-mediated immune (CMI) responses that help control HIV infection. In concept, ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.2555
更新日期:2007-02-10 00:00:00
abstract::When data are dichotomous, this paper notes the utility of inverse sampling in establishing equivalence with respect to the risk ratio. This paper develops an exact equivalence test that accounts for the risk ratio under inverse sampling and further discusses the relationship between the exact equivalence test and the...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19970815)16:15<1777::aid-s
更新日期:1997-08-15 00:00:00
abstract::Various aspects of portfolio management and project prioritization within the pharmaceutical industry are examined. It is shown that the cost and probability architecture of a project is a crucial aspect of its value. An appropriate simple tool for ranking projects is the Pearson index. Various difficulties are consid...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0258(19961230)15:24<2689::AID-S
更新日期:1996-12-30 00:00:00
abstract::The purpose of this research was to develop appropriate methods for analysing repeated ordinal categorical data that arose in an intervention trial to prevent oesophageal cancer. The measured response was the degree of oesophageal dysplasia at 2.5 and 6 years after randomization. An important feature was that some res...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780130511
更新日期:1994-03-15 00:00:00
abstract::Girardeau, Ravaud and Donner in 2008 presented a formula for sample size calculations for cluster randomised crossover trials, when the intracluster correlation coefficient, interperiod correlation coefficient and mean cluster size are specified in advance. However, in many randomised trials, the number of clusters is...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.8191
更新日期:2019-08-15 00:00:00
abstract::Multivariate random length data occur when we observe multiple measurements of a quantitative variable and the variable number of these measurements is also an observed outcome for each experimental unit. For example, for a patient with coronary artery disease, we may observe a number of lesions in that patient's coro...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19990130)18:2<199::aid-sim
更新日期:1999-01-30 00:00:00
abstract::The asymptotic Pearson's chi-squared test and Fisher's exact test have long been the most used for testing association in 2x2 tables. Unconditional tests preserve the significance level and generally are more powerful than Fisher's exact test for moderate to small samples, but previously were disadvantaged by being co...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3531
更新日期:2009-03-30 00:00:00