Abstract:
:Sample selection arises when the outcome of interest is partially observed in a study. Although sophisticated statistical methods in the parametric and non-parametric framework have been proposed to solve this problem, it is yet unclear how to deal with selectively missing covariate data using simple multiple imputation techniques, especially in the absence of exclusion restrictions and deviation from normality. Motivated by the 2003-2004 NHANES data, where previous authors have studied the effect of socio-economic status on blood pressure with missing data on income variable, we proposed the use of a robust imputation technique based on the selection-t sample selection model. The imputation method, which is developed within the frequentist framework, is compared with competing alternatives in a simulation study. The results indicate that the robust alternative is not susceptible to the absence of exclusion restrictions - a property inherited from the parent selection-t model - and performs better than models based on the normal assumption even when the data is generated from the normal distribution. Applications to missing outcome and covariate data further corroborate the robustness properties of the proposed method. We implemented the proposed approach within the MICE environment in R Statistical Software.
journal_name
Stat Methods Med Resjournal_title
Statistical methods in medical researchauthors
Ogundimu EO,Collins GSdoi
10.1177/0962280217715663subject
Has Abstractpub_date
2019-01-01 00:00:00pages
102-116issue
1eissn
0962-2802issn
1477-0334journal_volume
28pub_type
杂志文章abstract::In reliability theory, diagnostic accuracy, and clinical trials, the quantity P ( X > Y ) + ...
journal_title:Statistical methods in medical research
pub_type: 杂志文章
doi:10.1177/0962280220966629
更新日期:2020-12-01 00:00:00
abstract::In this paper, we develop a simple diagnostic test for the random-effects distribution in mixed models. The test is based on the gradient function, a graphical tool proposed by Verbeke and Molenberghs to check the impact of assumptions about the random-effects distribution in mixed models on inferences. Inference is c...
journal_title:Statistical methods in medical research
pub_type: 杂志文章
doi:10.1177/0962280214564721
更新日期:2017-04-01 00:00:00
abstract:BACKGROUND:Recent literature on the comparison of machine learning methods has raised questions about the neutrality, unbiasedness and utility of many comparative studies. Reporting of results on favourable datasets and sampling error in the estimated performance measures based on single samples are thought to be the m...
journal_title:Statistical methods in medical research
pub_type: 杂志文章
doi:10.1177/0962280213502437
更新日期:2016-10-01 00:00:00
abstract::Non-parametric linkage analysis examines similarities among affected relatives in alleles of one or more genetic markers (pieces of DNA at known locations on a chromosome). The objective is to evaluate departures from the null hypothesis that the markers are not near a disease gene. Under the null hypothesis, Mendel's...
journal_title:Statistical methods in medical research
pub_type: 杂志文章,评审
doi:10.1177/096228020101000103
更新日期:2001-02-01 00:00:00
abstract::The three-class Youden index serves both as a measure of medical test accuracy and a criterion to choose the optimal pair of cutoff values for classifying subjects into three ordinal disease categories (e.g. no disease, mild disease, advanced disease). We present a Bayesian nonparametric approach for estimating the th...
journal_title:Statistical methods in medical research
pub_type: 杂志文章
doi:10.1177/0962280217742538
更新日期:2018-03-01 00:00:00
abstract::Agreement between two methods of clinical measurement can be quantified using the differences between observations made using the two methods on the same subjects. The 95% limits of agreement, estimated by mean difference +/- 1.96 standard deviation of the differences, provide an interval within which 95% of differenc...
journal_title:Statistical methods in medical research
pub_type: 杂志文章,评审
doi:10.1177/096228029900800204
更新日期:1999-06-01 00:00:00
abstract::In cluster randomized trials, clusters of subjects are randomized rather than subjects themselves, and missing outcomes are a concern as in individual randomized trials. We assessed strategies for handling missing data when analysing cluster randomized trials with a binary outcome; strategies included complete case, a...
journal_title:Statistical methods in medical research
pub_type: 杂志文章
doi:10.1177/0962280214530030
更新日期:2016-12-01 00:00:00
abstract::Comparison of sequences that have descended from a common ancestor based on an explicit stochastic model of substitutions, insertions and deletions has risen to prominence in the last decade. Making statements about the positions of insertions-deletions (abbr. indels) is central in sequence and genome analysis and is ...
journal_title:Statistical methods in medical research
pub_type: 杂志文章
doi:10.1177/0962280208099500
更新日期:2009-10-01 00:00:00
abstract::Purpose The prevalence estimates of binary variables in sample surveys are often subject to two systematic errors: measurement error and nonresponse bias. A multiple-bias analysis is essential to adjust for both biases. Methods In this paper, we linked the latent class log-linear and proxy pattern-mixture models to ad...
journal_title:Statistical methods in medical research
pub_type: 杂志文章
doi:10.1177/0962280217690939
更新日期:2018-10-01 00:00:00
abstract::Trials run in either rare diseases, such as rare cancers, or rare sub-populations of common diseases are challenging in terms of identifying, recruiting and treating sufficient patients in a sensible period. Treatments for rare diseases are often designed for other disease areas and then later proposed as possible tre...
journal_title:Statistical methods in medical research
pub_type: 杂志文章
doi:10.1177/0962280216662070
更新日期:2018-05-01 00:00:00
abstract::Cancer patients are subject to multiple competing risks of death and may die from causes other than the cancer diagnosed. The probability of not dying from the cancer diagnosed, which is one of the patients' main concerns, is sometimes called the 'personal cure' rate. Two approaches of modelling competing-risk surviva...
journal_title:Statistical methods in medical research
pub_type: 杂志文章
doi:10.1177/0962280209347046
更新日期:2011-06-01 00:00:00
abstract::We consider two exact unconditional procedures to test the difference between two multinomials with ordered categorical data. Exact unconditional procedures are compared to other approaches based on the Wilcoxon mid-rank test and the proportional odds model. We use a real example from an arthritis pain study to illust...
journal_title:Statistical methods in medical research
pub_type: 杂志文章
doi:10.1177/0962280212450957
更新日期:2016-02-01 00:00:00
abstract::The analysis of health care costs is complicated by the skewed and heteroscedastic nature of their distribution with possibly additional zero values. Statistical methods that do not adjust for these features can lead to incorrect conclusions. This paper reviews recent developments in statistical methods for the analys...
journal_title:Statistical methods in medical research
pub_type: 杂志文章,评审
doi:10.1191/0962280202sm290ra
更新日期:2002-08-01 00:00:00
abstract::Pediatric cardiac surgery may lead to poor outcomes such as acute kidney injury (AKI) and prolonged hospital length of stay (LOS). Plasma and urine biomarkers may help with early identification and prediction of these adverse clinical outcomes. In a recent multi-center study, 311 children undergoing cardiac surgery we...
journal_title:Statistical methods in medical research
pub_type: 杂志文章
doi:10.1177/0962280214530608
更新日期:2016-12-01 00:00:00
abstract::Many statistical studies report p-values for inferential purposes. In several scenarios, the stochastic aspect of p-values is neglected, which may contribute to drawing wrong conclusions in real data experiments. The stochastic nature of p-values makes their use to examine the performance of given testing procedures o...
journal_title:Statistical methods in medical research
pub_type: 杂志文章
doi:10.1177/0962280217704451
更新日期:2018-12-01 00:00:00
abstract::In this paper we review methods of cluster analysis in the context of classifying patients on the basis of clinical and/or laboratory type observations. Both hierarchical and non-hierarchical methods of clustering are considered, although the emphasis is on the latter type, with particular attention devoted to the mix...
journal_title:Statistical methods in medical research
pub_type: 杂志文章,评审
doi:10.1177/096228029200100103
更新日期:1992-01-01 00:00:00
abstract::Immunotherapy, gene therapy or adoptive cell therapies, such as the chimeric antigen receptor+ T-cell therapies, have demonstrated promising therapeutic effects in oncology patients. We consider statistical designs for dose-finding adoptive cell therapy trials, in which the monotonic dose-response relationship assumed...
journal_title:Statistical methods in medical research
pub_type: 杂志文章
doi:10.1177/0962280220977009
更新日期:2020-12-16 00:00:00
abstract::Sample size calculations are needed to design and assess the feasibility of case-control studies. Although such calculations are readily available for simple case-control designs and univariate analyses, there is limited theory and software for multivariate unconditional logistic analysis of case-control data. Here we...
journal_title:Statistical methods in medical research
pub_type: 杂志文章
doi:10.1177/0962280217737157
更新日期:2019-03-01 00:00:00
abstract::Within paediatric populations, there may be distinct age groups characterised by different exposure-response relationships. Several regulatory guidance documents have suggested general age groupings. However, it is not clear whether these categorisations will be suitable for all new medicines and in all disease areas....
journal_title:Statistical methods in medical research
pub_type: 杂志文章
doi:10.1177/0962280220903751
更新日期:2020-09-01 00:00:00
abstract::We propose a hierarchical Bayesian methodology to model spatially or spatio-temporal clustered survival data with possibility of cure. A flexible continuous transformation class of survival curves indexed by a single parameter is used. This transformation model is a larger class of models containing two special cases ...
journal_title:Statistical methods in medical research
pub_type: 杂志文章
doi:10.1177/0962280212445658
更新日期:2016-02-01 00:00:00
abstract::The probability model for periodic screening was extended to provide statistical inference for sensitivity depending on sojourn time, in which the sensitivity was modeled as a function of time spent in the preclinical state and the sojourn time. The likelihood function with the proposed sensitivity model was then eval...
journal_title:Statistical methods in medical research
pub_type: 杂志文章
doi:10.1177/0962280212465499
更新日期:2016-04-01 00:00:00
abstract::For semi-continuous data which are a mixture of true zeros and continuously distributed positive values, the use of two-part mixed models provides a convenient modelling framework. However, deriving population-averaged (marginal) effects from such models is not always straightforward. Su et al. presented a model that ...
journal_title:Statistical methods in medical research
pub_type: 杂志文章
doi:10.1177/0962280213509798
更新日期:2016-10-01 00:00:00
abstract::To project national hepatitis C virus (HCV) burden, unbiased estimation of HCV progression to liver cirrhosis is required for the whole community of HCV-infected individuals. However, widely varying estimates of progression rates to cirrhosis have been produced. This disparity is partly associated with the statistical...
journal_title:Statistical methods in medical research
pub_type: 杂志文章
doi:10.1177/0962280208094688
更新日期:2009-06-01 00:00:00
abstract::Conditional two-part random-effects models have been proposed for the analysis of healthcare cost panel data that contain both zero costs from the non-users of healthcare facilities and positive costs from the users. These models have been extended to accommodate more flexible data structures when using the generalize...
journal_title:Statistical methods in medical research
pub_type: 杂志文章
doi:10.1177/0962280217690770
更新日期:2018-10-01 00:00:00
abstract:BACKGROUND:Dyspepsia diagnoses and treatment decisions are made in situations in which multiple factors must be taken into account. Evolving from neuro-biological insights, artificial neural networks (ANNs) can employ multiple factors in resolving medical prediction, classification, pattern recognition, and pattern com...
journal_title:Statistical methods in medical research
pub_type: 杂志文章
doi:10.1177/0962280206071839
更新日期:2007-08-01 00:00:00
abstract::Most diagnostic accuracy measures and criteria for selecting optimal cut-points are only applicable to diseases with binary or three stages. Currently, there exist two diagnostic measures for diseases with general k stages: the hypervolume under the manifold and the generalized Youden index. While hypervolume under th...
journal_title:Statistical methods in medical research
pub_type: 杂志文章
doi:10.1177/0962280215611631
更新日期:2017-12-01 00:00:00
abstract::In this paper, we describe a Bayesian hierarchical Poisson model for the prospective analysis of data for infectious diseases. The proposed model consists of two components. The first component describes the behavior of disease during nonepidemic periods and the second component represents the increase in disease coun...
journal_title:Statistical methods in medical research
pub_type: 杂志文章
doi:10.1177/0962280214527385
更新日期:2014-12-01 00:00:00
abstract::One of the main advantages of Bayesian analyses of clinical trials is their ability to formally incorporate skepticism about large treatment effects through the use of informative priors. We conducted a simulation study to assess the performance of informative normal, Student- t, and beta distributions in estimating r...
journal_title:Statistical methods in medical research
pub_type: 杂志文章
doi:10.1177/0962280215620828
更新日期:2018-01-01 00:00:00
abstract::Longitudinal zero-inflated count data are encountered frequently in substance-use research when assessing the effects of covariates and risk factors on outcomes. Often, both the time to a terminal event such as death or dropout and repeated measure count responses are collected for each subject. In this setting, the l...
journal_title:Statistical methods in medical research
pub_type: 杂志文章
doi:10.1177/0962280216659312
更新日期:2018-04-01 00:00:00
abstract::Two tests are proposed for checking the linearity of nonparametric function in partially linear models. The first one is based on a Crámer-von Mises statistic. This test can detect the local alternative converging to the null at the parametric rate 1/square root n. A bootstrap resample technique is provided to calcula...
journal_title:Statistical methods in medical research
pub_type: 杂志文章
doi:10.1191/0962280206sm440oa
更新日期:2006-06-01 00:00:00