Abstract：
BACKGROUND:Multiple Imputation as usually implemented assumes that data are Missing At Random (MAR), meaning that the underlying missing data mechanism, given the observed data, is independent of the unobserved data. To explore the sensitivity of the inferences to departures from the MAR assumption, we applied the method proposed by Carpenter et al. (2007).This approach aims to approximate inferences under a Missing Not At random (MNAR) mechanism by reweighting estimates obtained after multiple imputation where the weights depend on the assumed degree of departure from the MAR assumption. METHODS:The method is illustrated with epidemiological data from a surveillance system of hepatitis C virus (HCV) infection in France during the 2001-2007 period. The subpopulation studied included 4343 HCV infected patients who reported drug use. Risk factors for severe liver disease were assessed. After performing complete-case and multiple imputation analyses, we applied the sensitivity analysis to 3 risk factors of severe liver disease: past excessive alcohol consumption, HIV co-infection and infection with HCV genotype 3. RESULTS:In these data, the association between severe liver disease and HIV was underestimated, if given the observed data the chance of observing HIV status is high when this is positive. Inference for two other risk factors were robust to plausible local departures from the MAR assumption. CONCLUSIONS:We have demonstrated the practical utility of, and advocate, a pragmatic widely applicable approach to exploring plausible departures from the MAR assumption post multiple imputation. We have developed guidelines for applying this approach to epidemiological studies.
journal_name
BMC Med Res Methodoljournal_title
BMC medical research methodologyauthors
Héraud-Bousquet V,Larsen C,Carpenter J,Desenclos JC,Le Strat Ydoi
10.1186/1471-2288-12-73subject
Has Abstractpub_date
2012-06-08 00:00:00pages
73issn
1471-2288pii
1471-2288-12-73journal_volume
12pub_type
杂志文章abstract：BACKGROUND:When conducting a meta-analysis of a continuous outcome, estimated means and standard deviations from the selected studies are required in order to obtain an overall estimate of the mean effect and its confidence interval. If these quantities are not directly reported in the publications, they must be estima...
journal_title：BMC medical research methodology
pub_type： 杂志文章
doi：10.1186/s12874-015-0055-5
更新日期：2015-08-12 00:00:00
abstract：BACKGROUND:A key component of the implementation process is identifying potential barriers and facilitators that need to be addressed. The Theoretical Domains Framework (TDF) is one of the most commonly used frameworks for this purpose. When applying the TDF, it is critical to understand the context in which behaviours...
journal_title：BMC medical research methodology
pub_type： 杂志文章
doi：10.1186/s12874-020-01056-1
更新日期：2020-06-26 00:00:00
abstract：BACKGROUND:Emergency Departments (EDs) are a first point-of-contact for many youth with mental health and suicidality concerns and can serve as an effective recruitment source for randomized controlled trials (RCTs) of mental health interventions. However, recruitment in acute care settings is impeded by several challe...
journal_title：BMC medical research methodology
pub_type： 杂志文章
doi：10.1186/s12874-020-01117-5
更新日期：2020-09-14 00:00:00
abstract：BACKGROUND:Given an observed test statistic and its degrees of freedom, one may compute the observed P value with most statistical packages. It is unknown to what extent test statistics and P values are congruent in published medical papers. METHODS:We checked the congruence of statistical results reported in all the ...
journal_title：BMC medical research methodology
pub_type： 杂志文章
doi：10.1186/1471-2288-4-13
更新日期：2004-05-28 00:00:00
abstract：BACKGROUND:Chemotherapy is expected to reduce cancer deaths (CD), while possibly being harmful in terms of non-cancer deaths (NCD) because of toxicity. Peto's log-rank test is popular in the medical literature, but its operating characteristics are barely known. We compared this test to the most common ones in the stat...
journal_title：BMC medical research methodology
pub_type： 杂志文章
doi：10.1186/1471-2288-14-72
更新日期：2014-05-29 00:00:00
abstract：BACKGROUND:The development of risk prediction models is of increasing importance in medical research - their use in practice, however, is rare. Among other reasons this might be due to the fact that thorough validation is often lacking. This study focuses on two Bayesian approaches of how to validate a prediction rule ...
journal_title：BMC medical research methodology
pub_type： 杂志文章
doi：10.1186/1471-2288-12-99
更新日期：2012-07-20 00:00:00
abstract：BACKGROUND:Claims databases are generally considered inadequate for obesity research due to suboptimal capture of body mass index (BMI) measurements. This might not be true for bariatric surgery because of reimbursement requirements and changes in coding systems. We assessed the availability and validity of claims-base...
journal_title：BMC medical research methodology
pub_type： 杂志文章
doi：10.1186/s12874-020-01106-8
更新日期：2020-09-07 00:00:00
abstract：BACKGROUND:Postal self-completion questionnaires offer one of the least expensive modes of collecting patient based outcomes in health care research. The purpose of this review is to assess the efficacy of methods of increasing response to postal questionnaires in health care studies on patient populations. METHODS:Th...
journal_title：BMC medical research methodology
pub_type： 杂志文章,评审
doi：10.1186/1471-2288-6-5
更新日期：2006-02-23 00:00:00
abstract：BACKGROUND:Cross-cultural research with patient-reported outcomes measures (PROMs) assumes that the PROM in the target language will measure the same construct in the same way as the PROM in the source language. Yet translation methods are rarely used to qualitatively maximise construct equivalence or to describe the i...
journal_title：BMC medical research methodology
pub_type： 杂志文章
doi：10.1186/s12874-020-00962-8
更新日期：2020-05-26 00:00:00
abstract：BACKGROUND:Randomised controlled trials (RCTs) are the gold standard for evidence-based practice. However, RCTs can have limitations. For example, translation of findings into practice can be limited by design features, such as inclusion criteria, not accurately reflecting clinical populations. In addition, it is expen...
journal_title：BMC medical research methodology
pub_type： 杂志文章
doi：10.1186/s12874-020-01078-9
更新日期：2020-07-25 00:00:00
abstract：BACKGROUND:The intraclass correlation coefficient (ICC) is widely used in biomedical research to assess the reproducibility of measurements between raters, labs, technicians, or devices. For example, in an inter-rater reliability study, a high ICC value means that noise variability (between-raters and within-raters) is...
journal_title：BMC medical research methodology
pub_type： 杂志文章
doi：10.1186/1471-2288-14-121
更新日期：2014-11-22 00:00:00
abstract：BACKGROUND:Motivational Interviewing (MI), Brief Advice (BA) and Health Education (HE) are established smoking cessation induction methods for smokers with low desire to quit. Although randomized controlled trials (RCT's) have been frequently used to assess these interventions the temporal efficacy and effectiveness of...
journal_title：BMC medical research methodology
pub_type： 杂志文章,随机对照试验
doi：10.1186/s12874-018-0511-0
更新日期：2018-06-13 00:00:00
abstract：BACKGROUND:The purpose of this study was to determine the standard tasks performed by clinical research coordinators (CRCs) in oncology clinical trials. METHODS:Forty-one CRCs were anonymously surveyed, using a four-page self-administered questionnaire focused on demographics, qualifications, and professional experien...
journal_title：BMC medical research methodology
pub_type： 杂志文章
doi：10.1186/1471-2288-4-6
更新日期：2004-03-25 00:00:00
abstract：BACKGROUND:In longitudinal studies where subjects experience recurrent incidents over a period of time, such as respiratory infections, fever or diarrhea, statistical methods are required to take into account the within-subject correlation. METHODS:For repeated events data with censored failure, the independent increm...
journal_title：BMC medical research methodology
pub_type： 杂志文章
doi：10.1186/1471-2288-13-95
更新日期：2013-07-24 00:00:00
abstract：BACKGROUND:Diagnostic tests are performed in a subset of the population who are at higher risk, resulting in undiagnosed cases among those who do not receive the test. This poses a challenge for estimating the prevalence of the disease in the study population, and also for studying the risk factors for the disease. ME...
journal_title：BMC medical research methodology
pub_type： 杂志文章
doi：10.1186/s12874-017-0447-9
更新日期：2017-12-12 00:00:00
abstract：BACKGROUND:E1684 was the pivotal adjuvant melanoma trial for establishment of high-dose interferon (IFN) as effective therapy of high-risk melanoma patients. E1690 was an intriguing effort to corroborate E1684, and the differences between the outcomes of these trials have embroiled the field in controversy over the pas...
journal_title：BMC medical research methodology
pub_type： 杂志文章
doi：10.1186/1471-2288-12-183
更新日期：2012-11-29 00:00:00
abstract：BACKGROUND:Diagnostic problems in clinical trials are sometimes ordinal. For example, colon tumor staging was performed according to the TNM classification. However, clinical data are limited by markedly small sample sizes in some stage. METHODS:We propose a distribution-free test for detecting ordered alternatives in...
journal_title：BMC medical research methodology
pub_type： 杂志文章
doi：10.1186/1471-2288-13-148
更新日期：2013-12-05 00:00:00
abstract：BACKGROUND:The main objective of this paper is to compare different methods for predicting the levels of SO2 air pollution in oil and gas producing area of rural western Canada. Month-long average air quality measurements were collected over a two-year period (2001-2002) at multiple locations, with some side-by-side me...
journal_title：BMC medical research methodology
pub_type： 杂志文章
doi：10.1186/1471-2288-8-43
更新日期：2008-07-04 00:00:00
abstract：BACKGROUND:Outcomes in observational studies may not best estimate those expected in the HIV vaccine efficacy trials. We compared retention in Simulated HIV Vaccine Efficacy Trials (SiVETs) and observational cohorts drawn from two key populations in Uganda. METHODS:Two SiVETs were nested within two observational cohor...
journal_title：BMC medical research methodology
pub_type： 杂志文章
doi：10.1186/s12874-020-00920-4
更新日期：2020-02-12 00:00:00
abstract：BACKGROUND:Retaining participants in cohort studies with multiple follow-up waves is difficult. Commonly, researchers are faced with the problem of missing data, which may introduce biased results as well as a loss of statistical power and precision. The STROBE guidelines von Elm et al. (Lancet, 370:1453-1457, 2007); V...
journal_title：BMC medical research methodology
pub_type： 杂志文章,评审
doi：10.1186/1471-2288-12-96
更新日期：2012-07-11 00:00:00
abstract：BACKGROUND:The occurrence of communicable diseases (CD) depends on exposure to contagious persons. The effects of exposure to CD are delayed in time and contagious persons remain contagious for several days during which their contagiousness varies. Moreover when multiple exposures occur, it is difficult to know which e...
journal_title：BMC medical research methodology
pub_type： 杂志文章
doi：10.1186/1471-2288-13-26
更新日期：2013-02-20 00:00:00
abstract：BACKGROUND:It is widely recognised that the pursuit of sustainable development cannot be accomplished without addressing inequality, or observed differences between subgroups of a population. Monitoring health inequalities allows for the identification of health topics where major group differences exist, dimensions of...
journal_title：BMC medical research methodology
pub_type： 杂志文章
doi：10.1186/s12874-016-0229-9
更新日期：2016-10-19 00:00:00
abstract：BACKGROUND:Sickness absence (SA) is an important social, economic and public health issue. Identifying and understanding the determinants, whether biological, regulatory or, health services-related, of variability in SA duration is essential for better management of SA. The conditional frailty model (CFM) is useful whe...
journal_title：BMC medical research methodology
pub_type： 杂志文章
doi：10.1186/1471-2288-13-114
更新日期：2013-09-16 00:00:00
abstract：BACKGROUND:The Patient Reported Outcomes Measurement Information System 43-item short form (PROMIS-43) and the five-level EQ-5D (EQ-5D-5L) are recently developed measures of health-related quality of life (HRQL) that have potentially broad application in evaluating treatments and capturing burden of respiratory-related...
journal_title：BMC medical research methodology
pub_type： 杂志文章,多中心研究
doi：10.1186/1471-2288-14-78
更新日期：2014-06-16 00:00:00
abstract：BACKGROUND:Persistent Pseudomonas aeruginosa (PPA) infection promotes lung function deterioration in children with cystic fibrosis (CF). Although early CF diagnosis through newborn screening (NBS) has been shown to provide nutritional/growth benefit, it is unclear whether NBS lowers the risk of PPA infection and how th...
journal_title：BMC medical research methodology
pub_type： 杂志文章
doi：10.1186/s12874-016-0220-5
更新日期：2016-09-17 00:00:00
abstract：BACKGROUND:Generic quality of life (QoL) instruments provide important measures of self-reported wellbeing that can be compared across healthy and clinical populations. The aim of this analysis is to validate the ten-item QoL instrument "QOL10", as well as to confirm the validity of the embedded "QOL5" questionnaire an...
journal_title：BMC medical research methodology
pub_type： 杂志文章
doi：10.1186/s12874-016-0163-x
更新日期：2016-05-23 00:00:00
abstract：BACKGROUND:Amyotrophic Lateral Sclerosis (ALS), also known as Lou Gehrig's disease, is a rare disease with extreme between-subject variability, especially with respect to rate of disease progression. This makes modelling a subject's disease progression, which is measured by the ALS Functional Rating Scale (ALSFRS), ver...
journal_title：BMC medical research methodology
pub_type： 杂志文章
doi：10.1186/s12874-018-0479-9
更新日期：2018-02-06 00:00:00
abstract：BACKGROUND:Although a variety of instruments are available that capture stress experience, the assessment of chronic stress has been hindered by the lack of economical screening instruments. Recently, an English-language version of the Trier Inventory for Chronic Stress (TICS-EN) consisting of 57 items according to a s...
journal_title：BMC medical research methodology
pub_type： 杂志文章
doi：10.1186/s12874-020-01156-y
更新日期：2020-12-16 00:00:00
abstract：BACKGROUND:The use of health-related quality of life (HRQoL) as an endpoint in cancer clinical trials is growing rapidly. Hence, research into the statistical approaches used to analyze HRQoL data is of major importance, and could lead to a better understanding of the impact of treatments on the everyday life and care ...
journal_title：BMC medical research methodology
pub_type： 杂志文章,评审
doi：10.1186/s12874-017-0410-9
更新日期：2017-09-26 00:00:00
abstract：BACKGROUND:Evidence syntheses, and in particular systematic reviews (SRs), have become one of the cornerstones of evidence-based health care. The Assessment of Multiple Systematic Reviews (AMSTAR) tool has become the most widely used tool for investigating the methodological quality of SRs and is currently undergoing r...
journal_title：BMC medical research methodology
pub_type： 杂志文章
doi：10.1186/s12874-016-0183-6
更新日期：2016-08-26 00:00:00
