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 when repeated SA events occur within the same individual, as it allows simultaneous analysis of event dependence and heterogeneity due to unknown, unmeasured, or unmeasurable factors. However, its use may encounter computational limitations when applied to very large data sets, as may frequently occur in the analysis of SA duration. METHODS:To overcome the computational issue, we propose a Poisson-based conditional frailty model (CFPM) for repeated SA events that accounts for both event dependence and heterogeneity. To demonstrate the usefulness of the model proposed in the SA duration context, we used data from all non-work-related SA episodes that occurred in Catalonia (Spain) in 2007, initiated by either a diagnosis of neoplasm or mental and behavioral disorders. RESULTS:As expected, the CFPM results were very similar to those of the CFM for both diagnosis groups. The CPU time for the CFPM was substantially shorter than the CFM. CONCLUSIONS:The CFPM is an suitable alternative to the CFM in survival analysis with recurrent events, especially with large databases.
journal_name
BMC Med Res Methodoljournal_title
BMC medical research methodologyauthors
Torá-Rocamora I,Gimeno D,Delclos G,Benavides FG,Manzanera R,Jardí J,Alberti C,Yasui Y,Martínez JMdoi
10.1186/1471-2288-13-114subject
Has Abstractpub_date
2013-09-16 00:00:00pages
114issn
1471-2288pii
1471-2288-13-114journal_volume
13pub_type
杂志文章abstract:BACKGROUND:Small group research in healthcare is important because it deals with interaction and decision-making processes that can help to identify and improve safer patient treatment and care. However, the number of studies is limited due to time- and resource-intensive data processing. The aim of this study was to e...
journal_title:BMC medical research methodology
pub_type: 杂志文章
doi:10.1186/s12874-019-0756-2
更新日期:2019-06-13 00:00:00
abstract:BACKGROUND:The Community Reintegration of Service Members (CRIS) is a new measure of community reintegration developed to measure veteran's participation in life roles. It consists of three sub-scales: Extent of Participation (Extent), Perceived Limitations with Participation (Perceived), and Satisfaction with Particip...
journal_title:BMC medical research methodology
pub_type: 杂志文章,随机对照试验
doi:10.1186/1471-2288-11-98
更新日期:2011-06-25 00:00:00
abstract:BACKGROUND:Missing data are common in medical research, which can lead to a loss in statistical power and potentially biased results if not handled appropriately. Multiple imputation (MI) is a statistical method, widely adopted in practice, for dealing with missing data. Many academic journals now emphasise the importa...
journal_title:BMC medical research methodology
pub_type: 杂志文章,评审
doi:10.1186/s12874-015-0022-1
更新日期:2015-04-07 00:00:00
abstract:BACKGROUND:Models of hepatitis C virus (HCV) kinetics are increasingly used to estimate and to compare in vivo drug's antiviral effectiveness of new potent anti-HCV agents. Viral kinetic parameters can be estimated using non-linear mixed effect models (NLMEM). Here we aimed to evaluate the performance of this approach ...
journal_title:BMC medical research methodology
pub_type: 杂志文章
doi:10.1186/1471-2288-13-60
更新日期:2013-04-25 00:00:00
abstract:BACKGROUND:Physical activity is an important determinant of health. Walking is the most common physical activity performed by adults and the presence of sidewalks along roads is a determinant of walking. Geographic information systems (GIS) can be used to measure sidewalks; however, GIS sidewalk data are difficult to a...
journal_title:BMC medical research methodology
pub_type: 杂志文章
doi:10.1186/1471-2288-12-39
更新日期:2012-03-29 00:00:00
abstract:BACKGROUND:In a random effects meta-analysis model, true treatment effects for each study are routinely assumed to follow a normal distribution. However, normality is a restrictive assumption and the misspecification of the random effects distribution may result in a misleading estimate of overall mean for the treatmen...
journal_title:BMC medical research methodology
pub_type: 杂志文章
doi:10.1186/s12874-017-0376-7
更新日期:2017-07-19 00:00:00
abstract:BACKGROUND:Although some nonparametric methods have been proposed in the literature to test for the equality of median survival times for censored data in medical research, in general they have inflated type I error rates, which make their use limited in practice, especially when the sample sizes are small. METHODS:In...
journal_title:BMC medical research methodology
pub_type: 杂志文章
doi:10.1186/s12874-016-0133-3
更新日期:2016-03-16 00:00:00
abstract:BACKGROUND:In spite of efforts to employ risk-based strategies to increase monitoring efficiency in the academic setting, empirical evidence on their effectiveness remains sparse. This mixed-methods study aimed to evaluate the risk-based on-site monitoring approach currently followed at our academic institution. METHO...
journal_title:BMC medical research methodology
pub_type: 杂志文章
doi:10.1186/s12874-017-0308-6
更新日期:2017-02-14 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: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:In many studies the information of patients who are dying in the hospital is censored when examining the change in length of hospital stay (cLOS) due to hospital-acquired infections (HIs). While appropriate estimators of cLOS are available in literature, the existence of the bias due to censoring of deaths w...
journal_title:BMC medical research methodology
pub_type: 杂志文章
doi:10.1186/s12874-018-0500-3
更新日期:2018-05-30 00:00:00
abstract:BACKGROUND:Multilevel models for non-normal outcomes are widely used in medical and health sciences research. While methods for interpreting fixed effects are well-developed, methods to quantify and interpret random cluster variation and compare it with other sources of variation are less established. Random cluster va...
journal_title:BMC medical research methodology
pub_type: 杂志文章
doi:10.1186/s12874-018-0517-7
更新日期:2018-07-06 00:00:00
abstract:BACKGROUND:Plasma cell dyscrasias (PCD) are a spectrum of disorders resulting from the clonal expansion of plasma cells, ranging from the pre-malignant condition monoclonal gammopathy of undetermined significance (MGUS) to multiple myeloma (MM). MM generates a significant burden of disease on the community and it is pr...
journal_title:BMC medical research methodology
pub_type: 杂志文章
doi:10.1186/s12874-016-0250-z
更新日期:2016-11-09 00:00:00
abstract:BACKGROUND:Diabetes-related lower limb amputations are associated with considerable morbidity and mortality and are usually preceded by foot ulceration. The available systematic reviews of aggregate data are compromised because the primary studies report both adjusted and unadjusted estimates. As adjusted meta-analyses...
journal_title:BMC medical research methodology
pub_type: 杂志文章,meta分析
doi:10.1186/1471-2288-13-22
更新日期:2013-02-15 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:Clinical study reports (CSRs) have been increasingly utilised within academic research in recent years. European Medicines Agency (EMA) Policy 0070 'Phase 1,' which came into effect in January 2015, requires the publication of regulatory documents such as CSRs from central applications in an anonymised forma...
journal_title:BMC medical research methodology
pub_type: 杂志文章,评审
doi:10.1186/s12874-019-0836-3
更新日期:2019-11-05 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: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:The Template for Intervention Description and Replication (TIDieR) checklist and guide was developed by an international team of experts to promote full and accurate description of trial interventions. It is now widely used in health research. The aim of this paper is to describe the experience of using TIDi...
journal_title:BMC medical research methodology
pub_type: 杂志文章
doi:10.1186/s12874-017-0461-y
更新日期:2018-01-18 00:00:00
abstract:BACKGROUND:Dichotomisation of continuous outcomes has been rightly criticised by statisticians because of the loss of information incurred. However to communicate a comparison of risks, dichotomised outcomes may be necessary. Peacock et al. developed a distributional approach to the dichotomisation of normally distribu...
journal_title:BMC medical research methodology
pub_type: 杂志文章
doi:10.1186/s12874-015-0028-8
更新日期:2015-04-24 00:00:00
abstract:BACKGROUND:Studies examining incident heart failure (HF) have been limited to select populations. To examine incident HF with broader generalizability, there is need to assemble a HF-free cohort using a geographically-diverse sample. We aimed to develop and validate a simple medication-based strategy for assembling a H...
journal_title:BMC medical research methodology
pub_type: 杂志文章
doi:10.1186/s12874-019-0890-x
更新日期:2020-03-04 00:00:00
abstract:BACKGROUND:In recent months, multiple efforts have sought to characterize COVID-19 social distancing policy responses. These efforts have used various coding frameworks, but many have relied on coding methodologies that may not adequately describe the gradient in social distancing policies as states "re-open." METHODS...
journal_title:BMC medical research methodology
pub_type: 杂志文章
doi:10.1186/s12874-020-01174-w
更新日期:2020-12-08 00:00:00
abstract:BACKGROUND:Systematic reviewers seek to comprehensively search for relevant studies and summarize these to present the most valid estimate of intervention effectiveness. The more resources searched, the higher the yield, and thus time and costs required to conduct a systematic review. While there is an abundance of evi...
journal_title:BMC medical research methodology
pub_type: 杂志文章,评审
doi:10.1186/1471-2288-5-24
更新日期:2005-08-10 00:00:00
abstract:BACKGROUND:Compelled by the intuitive appeal of predicting each individual patient's risk of an outcome, there is a growing interest in risk prediction models. While the statistical methods used to build prediction models are increasingly well understood, the literature offers little insight to researchers seeking to g...
journal_title:BMC medical research methodology
pub_type: 杂志文章
doi:10.1186/s12874-016-0223-2
更新日期:2016-09-21 00:00:00
abstract:BACKGROUND:Quantitative Microbial Risk Assessment (QMRA), a modelling approach, is used to assess health risks. Inputs into the QMRA process include data that characterise the intensity, frequency and duration of exposure to risk(s). Data gaps for water exposure assessment include the duration and frequency of urban no...
journal_title:BMC medical research methodology
pub_type: 杂志文章
doi:10.1186/1471-2288-9-72
更新日期:2009-11-09 00:00:00
abstract:BACKGROUND:The study design and protocol that underpin a randomised controlled trial (RCT) are critical for the ultimate success of the trial. Although RCTs are considered the gold standard for research, there are multiple threats to their validity such as participant recruitment and retention, identifying a meaningful...
journal_title:BMC medical research methodology
pub_type: 杂志文章
doi:10.1186/s12874-019-0772-2
更新日期:2019-06-18 00:00:00
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 meth...
journal_title:BMC medical research methodology
pub_type: 杂志文章
doi:10.1186/1471-2288-12-73
更新日期:2012-06-08 00:00:00
abstract:BACKGROUND:Epidemiologic studies often struggle to adequately represent populations and outcomes of interest. Differences in methodology, data analysis and research questions often mean that reviews and synthesis of the existing literature have significant limitations. The current paper details our experiences in combi...
journal_title:BMC medical research methodology
pub_type: 杂志文章
doi:10.1186/1471-2288-13-122
更新日期:2013-10-05 00:00:00
abstract:BACKGROUND:In prognostic studies model instability and missing data can be troubling factors. Proposed methods for handling these situations are bootstrapping (B) and Multiple imputation (MI). The authors examined the influence of these methods on model composition. METHODS:Models were constructed using a cohort of 58...
journal_title:BMC medical research methodology
pub_type: 杂志文章
doi:10.1186/1471-2288-10-81
更新日期:2010-09-17 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