Abstract:
:Estimates of transmission probabilities for sexually transmitted diseases historically come from studies of uninfected individuals exposed to those with a high disease prevalence (for example, prostitutes). However, changes in sexual behaviour, much of which relates to concerns about AIDS, has made identification of populations suitable for such studies extremely difficult. This paper presents a method for estimating these probabilities that utilizes a deterministic model and routinely collected data available in many clinics. Variance estimates for the estimators are also derived. Data for chlamydial infection and sensitivity analyses for the input parameters and assumptions illustrate the method.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Katz BPdoi
10.1002/sim.4780110502subject
Has Abstractpub_date
1992-03-01 00:00:00pages
565-77issue
5eissn
0277-6715issn
1097-0258journal_volume
11pub_type
杂志文章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::Conditional power based on summary statistic by comparing outcomes (such as the sample mean) directly between 2 groups is a convenient tool for decision making in randomized controlled trial studies. In this paper, we extend the traditional summary statistic-based conditional power with a general model-based assessmen...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.7454
更新日期:2017-12-30 00:00:00
abstract:BACKGROUND:The need to deliver interventions targeting multiple diseases in a cost-effective manner calls for integrated disease control efforts. Consequently, maps are required that show where the risk of co-infection is particularly high. Co-infection risk is preferably estimated via Bayesian geostatistical multinomi...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4243
更新日期:2011-06-30 00:00:00
abstract::We applied a computationally practical form of probit analysis for multiple response variables to data on early childhood development of four psychiatric disorders: disruptive disorders (DD-attention deficit disorders, oppositional defiant disorder, conduct disorder); adjustment disorders (ADJ); emotional disorders (E...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19981115)17:21<2487::aid-s
更新日期:1998-11-15 00:00:00
abstract::Sexually transmitted infections (STIs) with Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis are among the most common infectious diseases in the United States, disproportionately affecting young women. Because a significant portion of the infections present no symptoms, infection control relies...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6515
更新日期:2015-09-10 00:00:00
abstract::Missing data arise in crossover trials, as they do in any form of clinical trial. Several papers have addressed the problems that missing data create, although almost all of these assume that the probability that a planned observation is missing does not depend on the value that would have been observed; that is, the ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4497
更新日期:2012-07-20 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::We develop a simulation-based procedure for determining the required sample size in binomial regression risk assessment studies when response data are subject to misclassification. A Bayesian average power criterion is used to determine a sample size that provides high probability, averaged over the distribution of po...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3505
更新日期:2009-02-28 00:00:00
abstract::The development of drugs and biologicals whose mechanisms of action may extend beyond their target indications has led to a need to identify unexpected potential toxicities promptly even while blinded clinical trials are under way. One component of recently issued FDA rules regarding safety reporting requirements rais...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.7129
更新日期:2017-01-15 00:00:00
abstract::Regression to the mean arises often in statistical applications where the units chosen for study relate to some observed characteristic in the extreme of its distribution. Gardner and Heady attribute the effect of regression to the mean to measurement errors. They assume the model Yi = U + ei, where U is a fixed withi...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780100812
更新日期:1991-08-01 00:00:00
abstract::In biomedical literature, numerous prediction models for clinical outcomes have been developed based either on clinical data or, more recently, on high-throughput molecular data (omics data). Prediction models based on both types of data, however, are less common, although some recent studies suggest that a suitable c...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6246
更新日期:2014-12-30 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::Hot-deck imputation is an intuitively simple and popular method of accommodating incomplete data. Users of the method will often use the usual multiple imputation variance estimator which is not appropriate in this case. However, no variance expression has yet been derived for this easily implemented method applied to...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19970115)16:1<5::aid-sim46
更新日期:1997-01-15 00:00:00
abstract::To study the spread of sexually transmitted diseases (STDs) using social/sexual mixing models, one must have quantitative information about sexual mixing. An unavoidable complication in gathering such information by survey is that members of the surveyed population will almost certainly have sexual contacts outside th...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780111202
更新日期:1992-09-15 00:00:00
abstract::Rationalization of antibiotic therapy in the management of infectious diseases is helped by a knowledge of the patterns of sensitivity and resistance of bacteria to antibiotics and their possible changes both in time and from one hospital unit to another. In this paper we present the results regarding the sensitivitie...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.2447
更新日期:2006-10-30 00:00:00
abstract::We propose the use of Gaussian mixed models to analyse statistically 24 hour ambulatory blood pressure data from clinical trials. We develop specific models and apply them to data from a clinical study that compares two angiotensin-converting enzyme inhibitors. We investigate and discuss computing issues related to th...
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.4780121803
更新日期:1993-09-30 00:00:00
abstract::Ordinal data appear in a wide variety of scientific fields. These data are often analyzed using ordinal logistic regression models that assume proportional odds. When this assumption is not met, it may be possible to capture the lack of proportionality using a constrained structural relationship between the odds and t...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5689
更新日期:2013-06-15 00:00:00
abstract::In Part I we presented a covariance structure model for analysing measurement error in the assessment of nitrogen intake. In this paper we include data on urine nitrogen excretion which allows a critical assessment of the model proposed. Inclusion of urine nitrogen data produces more pessimistic estimates of the quali...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780121005
更新日期:1993-05-30 00:00:00
abstract::Conditional power and predictive power provide estimates of the probability of success at the end of the trial based on the information from the interim analysis. The observed value of the time to event endpoint at the interim analysis could be biased for the true treatment effect due to early censoring, leading to a ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.7673
更新日期:2018-08-15 00:00:00
abstract::Important differences between explanatory and pragmatic studies were originally argued by Schwartz and Lellouch. Three important differences between the two types of study involve study control, study violators and inclusion criteria. It was originally argued that explanatory studies are highly controlled, and pragmat...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.1120
更新日期:2002-05-30 00:00:00
abstract::Hierarchical regression analysis holds much promise for epidemiologic analysis, but has as yet seen limited application because of lack of easily used software and the relatively lengthy run times of preferred fitting methods (such as true maximum likelihood and Bayesian approaches). This paper compares three relative...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19970315)16:5<515::aid-sim
更新日期:1997-03-15 00:00:00
abstract::Observational studies provide a rich source of information for assessing effectiveness of treatment interventions in many situations where it is not ethical or practical to perform randomized controlled trials. However, such studies are prone to bias from hidden (unmeasured) confounding. A promising approach to identi...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.7051
更新日期:2016-12-10 00:00:00
abstract::The use of both sequential designs and adaptive treatment allocation are effective in reducing the number of patients receiving an inferior treatment in a clinical trial. In large samples, when the asymptotic normality of test statistics can be utilized, a standard sequential design can be combined with adaptive alloc...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.998
更新日期:2002-02-28 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::Slow recruitment in clinical trials leads to increased costs and resource utilization, which includes both the clinic staff and patient volunteers. Careful planning and monitoring of the accrual process can prevent the unnecessary loss of these resources. We propose two hierarchical extensions to the existing Bayesian...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6359
更新日期:2015-02-20 00:00:00
abstract::Many critical questions in medicine require the analysis of complex multivariate data, often from large data sets describing numerous variables for numerous subjects. In this paper, we describe CoPlot, a tool for visualizing multivariate data in medicine. CoPlot is an adaptation of multidimensional scaling (MDS) that ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3078
更新日期:2008-05-30 00:00:00
abstract::In time-to-event analysis, the traditional summary measures have been based on the hazard function, survival function, quantile event time, restricted mean event time, and residual lifetime. Under competing risks, furthermore, typical summary measures have been the cause-specific hazard function and cumulative inciden...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.8871
更新日期:2021-01-06 00:00:00
abstract::Many neuroscientists are interested in how connectomes (graphical representations of functional connectivity between areas of the brain) change in relation to covariates. In statistics, changes like this are analyzed using regression, where the outcomes or dependent variables are regressed onto the covariates. However...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.8374
更新日期:2019-12-20 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::Generalized relative and absolute risk models, in which various functions of time and age modify the excess relative or absolute risk of radiation-induced cancer, are fitted to the Japanese atomic bomb survivor cancer incidence data set. Among generalized relative risk models, those in which a product of powers of tim...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19990115)18:1<17::aid-sim9
更新日期:1999-01-15 00:00:00