Abstract:
:We analyze data obtained from a study designed to evaluate training effects on the performance of certain motor activities of Parkinson's disease patients. Maximum likelihood methods were used to fit beta-binomial/Poisson regression models tailored to evaluate the effects of training on the numbers of attempted and successful specified manual movements in 1 min periods, controlling for disease stage and use of the preferred hand. We extend models previously considered by other authors in univariate settings to account for the repeated measures nature of the data. The results suggest that the expected number of attempts and successes increase with training, except for patients with advanced stages of the disease using the non-preferred hand.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Lora MI,Singer JMdoi
10.1002/sim.3303subject
Has Abstractpub_date
2008-07-30 00:00:00pages
3366-81issue
17eissn
0277-6715issn
1097-0258journal_volume
27pub_type
杂志文章abstract::A few large multi-centre male-only heart trials done in the 1970s and 1980s have been seen as ill-conceived because they did not include females. The purpose here is to revisit two of those trials and to consider consequences in terms of cost and power had they been designed to include females. ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19990215)18:3<241::aid-sim
更新日期:1999-02-15 00:00:00
abstract::This paper assesses the coverage probability of commonly used confidence intervals for the standardized mortality ratio (SMR) when death certificates are missing. It also proposes alternative confidence interval approaches with coverage probabilities close to .95. In epidemiology, the SMR is an important measure of ri...
journal_title:Statistics in medicine
pub_type: 杂志文章
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abstract::A preference trial is a special form of cross-over trial where clinical conditions determine when patients change treatment, in a prescribed order. This can be modelled using a geometric distribution. The model can be simply fitted using standard logistic regression methodology. The procedure is applied to a trial stu...
journal_title:Statistics in medicine
pub_type: 杂志文章
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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::Biomedical studies often measure variables with error. Examples in the literature include investigation of the association between the change in some outcome variable (blood pressure, cholesterol level etc.) and a set of explanatory variables (age, smoking status etc.). Typically, one fits linear regression models to ...
journal_title:Statistics in medicine
pub_type: 杂志文章
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更新日期:1998-11-30 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
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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
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.8038
更新日期:2019-03-30 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
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更新日期:1992-01-30 00:00:00
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journal_title:Statistics in medicine
pub_type: 临床试验,杂志文章,随机对照试验
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更新日期:1995-07-30 00:00:00
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journal_title:Statistics in medicine
pub_type: 临床试验,杂志文章,随机对照试验
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更新日期:2000-01-15 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19990715)18:13<1575::aid-s
更新日期:1999-07-15 00:00:00
abstract::Methods for addressing multiplicity in clinical trials have attracted much attention during the past 20 years. They include the investigation of new classes of multiple test procedures, such as fixed sequence, fallback and gatekeeping procedures. More recently, sequentially rejective graphical test procedures have bee...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5711
更新日期:2013-05-10 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
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journal_title:Statistics in medicine
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doi:10.1002/sim.7952
更新日期:2019-01-15 00:00:00
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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
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5405
更新日期:2012-11-10 00:00:00
abstract::A new exponentially weighted moving average (EWMA) control chart well suited for 'online' routine surveillance of medical procedures is introduced. The chart is based on inter-event counts for failures recorded when the failures occur. The method can be used for many types of hospital procedures and activities, such a...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.2520
更新日期:2007-01-15 00:00:00
abstract::We propose a goodness-of-fit test statistic for linear regression with heterogeneous variance, which is asymptotically chi-square if the given model is correct. The test statistic is computed as a quadratic form of observed minus predicted responses. We apply the method to a linear regression for an ordinal categorica...
journal_title:Statistics in medicine
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doi:10.1002/sim.4780130205
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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
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journal_title:Statistics in medicine
pub_type: 杂志文章
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更新日期:2010-03-15 00:00:00
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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
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journal_title:Statistics in medicine
pub_type: 杂志文章
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更新日期:2013-12-10 00:00:00
abstract::In contrast to other models for ordinal data, the continuation ratio model can be fitted with standard statistical software. This makes it particularly appropriate for large clinical trials with ordinal response variables. In addition, when the trials are longitudinal, this model can be applied to individual responses...
journal_title:Statistics in medicine
pub_type: 临床试验,杂志文章,随机对照试验
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更新日期:1997-12-30 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19980715)17:13<1425::aid-s
更新日期:1998-07-15 00:00:00
abstract::Estimation of genetic and environmental contributions to cancers falls in the framework of generalized linear mixed modelling with several random effect components. Computational challenges remain, however, in dealing with binary or survival phenotypes. In this paper, we consider the analysis of melanoma onset in a po...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.2266
更新日期:2006-09-30 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19990315)18:5<539::aid-sim
更新日期:1999-03-15 00:00:00
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journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780090707
更新日期:1990-07-01 00:00:00