Abstract:
:This paper presents a statistical analysis of treatment effects in 24-hour ambulatory blood pressure recordings. The statistical models account for circadian rhythms, subject effects, and the effects of treatment with drugs or relaxation therapy. In view of the heterogeneity of the subjects, we fit a separate linear model to the data of each subject, use robust statistical procedures to estimate the parameters of the linear models, and trim the data on a subject by subject basis. We use a meta-analytical method to combine the results of all subjects in the study.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Marler MR,Jacob RG,Lehoczky JP,Shapiro APdoi
10.1002/sim.4780070608subject
Has Abstractpub_date
1988-06-01 00:00:00pages
697-716issue
6eissn
0277-6715issn
1097-0258journal_volume
7pub_type
杂志文章abstract::This paper investigates the impact on area life tables of the specification of unobserved frailty. Frailty specification may affect both the regression effects of area and individual level covariates, and lead to changes in the value of summary mortality parameters, such as life expectancy. The paper also investigates...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780141703
更新日期:1995-09-15 00:00:00
abstract::We present graphical and numerical methods for assessing the adequacy of the logistic regression model for stratified case-control data. The proposed methods are derived from the cumulative sum of residuals over the covariate or linear predictor. Under the assumed model, the cumulative residual process converges weakl...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.1932
更新日期:2005-01-30 00:00:00
abstract::Incomplete and unbalanced multivariate data often arise in longitudinal studies due to missing or unequally-timed repeated measurements and/or the presence of time-varying covariates. A general approach to analysing such data is through maximum likelihood analysis using a linear model for the expected responses, and s...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780070132
更新日期:1988-01-01 00:00:00
abstract::This field study sought to measure the effects of dental delivery and school-based, dental health education on use of dental health care by children in grades K-6. We attempted to control for two potential confounding factors by an approximate randomization of children into treatment groups with stratification on grad...
journal_title:Statistics in medicine
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1002/sim.4780020107
更新日期:1983-01-01 00:00:00
abstract::Kappa coefficients are measures of correlation between categorical variables often used as reliability or validity coefficients. We recapitulate development and definitions of the K (categories) by M (ratings) kappas (K x M), discuss what they are well- or ill-designed to do, and summarize where kappas now stand with ...
journal_title:Statistics in medicine
pub_type: 杂志文章,评审
doi:10.1002/sim.1180
更新日期:2002-07-30 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::Day and Walter derived methods of joint maximum likelihood estimation for the sojourn time distribution and the false negative rate for a screening programme. Their methods are not directly applicable to a programme which uses alternate screening by two modalities whose sojourn times and false negative rates will diff...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780080611
更新日期:1989-06-01 00:00:00
abstract::Assessment of equivalence or non-inferiority in accuracy between two diagnostic procedures often involves comparisons of paired areas under the receiver operating characteristic (ROC) curves. With some pre-specified clinically meaningful limits, the current approach to evaluating equivalence is to perform the two one-...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.2358
更新日期:2006-04-15 00:00:00
abstract::The identification of changes in the recent trend is an important issue in the analysis of cancer mortality and incidence data. We apply a joinpoint regression model to describe such continuous changes and use the grid-search method to fit the regression function with unknown joinpoints assuming constant variance and ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(20000215)19:3<335::aid-sim
更新日期:2000-02-15 00:00:00
abstract::The incremental life expectancy, defined as the difference in mean survival times between two treatment groups, is a crucial quantity of interest in cost-effectiveness analyses. Usually, this quantity is very difficult to estimate from censored survival data with a limited follow-up period. The paper develops estimati...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6951
更新日期:2016-09-10 00:00:00
abstract::Statistical methods are available for performing a meta-analysis when the response variable of interest is the same in each study. Problems arise when studies exploring a common therapeutic question use different patient response types. This article presents statistical methods for combining studies which involve diff...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780132313
更新日期:1994-12-15 00:00:00
abstract::In this paper, we consider a full likelihood method to analyze continuous longitudinal responses with non-ignorable non-monotone missing data. We consider a transition probability model for the missingness mechanism. A first-order Markov dependence structure is assumed for both the missingness mechanism and observed d...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5359
更新日期:2012-12-10 00:00:00
abstract::We applied a two-stage random effects model to pulmonary function data from 31 sarcoidosis patients to illustrate its usefulness in analysing unbalanced longitudinal data. For the first stage, repeated measurements of percentage of predicted forced vital capacity (FVC%) from an individual were modelled as a function o...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780080206
更新日期:1989-02-01 00:00:00
abstract::The sojourn time, time spent in the preclinical detectable phase (PCDP) for chronic diseases, for example, breast cancer, plays an important role in the design and assessment of screening programmes. Traditional methods to estimate it usually assume a uniform incidence rate of preclinical disease from a randomized con...
journal_title:Statistics in medicine
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1002/sim.4780141404
更新日期:1995-07-30 00:00:00
abstract::In many community-based studies on the incidence of dementia, a target population is screened and a subsample is clinically evaluated at baseline and follow-up. Incidence rates are affected by missed cases at both exams and this complicates the estimation of these rates. Recent work proposes a regression-based techniq...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(20000615/30)19:11/12<1577:
更新日期:2000-06-15 00:00:00
abstract::Most phase I dose-finding methods in oncology aim to find the maximum-tolerated dose from a set of prespecified doses. However, in practice, because of a lack of understanding of the true dose-toxicity relationship, it is likely that none of these prespecified doses are equal or reasonably close to the true maximum-to...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6933
更新日期:2016-09-10 00:00:00
abstract::We analyse the effect of using prevalence rates based on populations with different sizes in the power of spatial independence tests. We compare the well known spatial correlation Moran's index to three indexes obtained after adjusting for population density, one proposed by Oden, another proposed by Waldhör, and a th...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19990830)18:16<2147::aid-s
更新日期:1999-08-30 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::This paper presents tables analogous to T-tables for use in the 2 x 2 multinomial trial, where the continuity corrected Z-statistic is used to make exact unconditional inference. This is the first solution of a discrete exact unconditional inference problem involving a multivariate nuisance parameter for which no anci...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780110708
更新日期:1992-05-01 00:00:00
abstract::Clinical trials of treatments for rare or fatal diseases must often use historical rather than randomized concurrent controls. Randomized trials may not be possible if (1) the number of patients available is quite small, (2) ethical considerations discourage the assignment of patients to control treatments known to be...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780030305
更新日期:1984-07-01 00:00:00
abstract::The validity and practical utility of observational medical research depends critically on good study design, excellent data quality, appropriate statistical methods and accurate interpretation of results. Statistical methodology has seen substantial development in recent times. Unfortunately, many of these methodolog...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6265
更新日期:2014-12-30 00:00:00
abstract::In this article, we investigate procedures for comparing two independent Poisson variates that are observed over unequal sampling frames (i.e. time intervals, populations, areas or any combination thereof). We consider two statistics (with and without the logarithmic transformation) for testing the equality of two Poi...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.1949
更新日期:2005-03-30 00:00:00
abstract::Two important qualities of controlled clinical trials are that they reduce dependence on historical standards for evaluating therapy and separate the effect of treatment from the confounding influence of time. Whatever the theory of the clinical trial, however, time has not easily been banished from the analysis of me...
journal_title:Statistics in medicine
pub_type: 杂志文章,评审
doi:10.1002/sim.4780081106
更新日期:1989-11-01 00:00:00
abstract::I discuss alternatives to the one compartment model, delta Yt = alpha + beta exp(- gamma t). Instead of comparing the one and two compartment models, I derive statistics for testing mixtures of the parameters (beta, gamma) in the one compartment model. I apply the proposed methods to the problem of hydrogen clearance ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780080811
更新日期:1989-08-01 00:00:00
abstract::The primary purpose of a disease surveillance system is to provide data for the detection of changes in the incidence of the disease. Methods for the analysis of data from surveillance systems are reviewed. A new procedure is proposed for use when the system includes geographically dispersed reporting units, such as h...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780080306
更新日期:1989-03-01 00:00:00
abstract::Although all clinical trials are designed and monitored using more than one endpoint, methods are needed to assure that decision criteria are chosen to reflect the clinically relevant tradeoffs that assure the trial's scientific integrity. This article presents a framework for the design and monitoring clinical trials...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.8696
更新日期:2020-11-20 00:00:00
abstract::We extend the shared frailty model of recurrent events and a dependent terminal event to allow for a nonparametric covariate function. We include a Gaussian random effect (frailty) in the intensity functions of both the recurrent and terminal events to capture correlation between the two processes. We employ the penal...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4297
更新日期:2011-09-30 00:00:00
abstract::In order for national statistical offices to maintain the trust of the public to collect data and publish statistics of importance to society and decision-making, it is imperative that respondents (persons or establishments) be guaranteed privacy and confidentiality in return for providing requested confidential data....
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.2043
更新日期:2005-02-28 00:00:00
abstract::Clinical trials often assess therapeutic benefit on the basis of an event such as death or the diagnosis of disease. Usually, there are several additional longitudinal measures of clinical status which are collected to be used in the treatment comparison. This paper proposes a simple non-parametric test which combines...
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(19990615)18:11<1341::aid-s
更新日期:1999-06-15 00:00:00
abstract::Testing the equality of 2 proportions for a control group versus a treatment group is a well-researched statistical problem. In some settings, there may be strong historical data that allow one to reliably expect that the control proportion is one, or nearly so. While one-sample tests or comparisons to historical cont...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.7579
更新日期:2018-03-30 00:00:00