The propensity score adjusted hazard ratio between maternal smoking during pregnancy and having no smoker in the family was 1.10 (0.97 to 1.25). (bmj.com)
The multivariate analysis showed that the risk of mortality was significantly higher for the non-progressive patients who stopped at 6 cycles (standard protocol) than those who continued the treatment, hazard ratio = 1.5 (95% CI 1.2-1.9). (springer.com)
Time to stable culture conversion in liquid media was faster in the 35 mg/kg rifampicin group than in the control group (median 48 days vs 62 days, adjusted hazard ratio 1.78;95% CI 1.22-2.58, p=0.003), but not in other experimental arms. (uni-muenchen.de)
On survival analysis the lowest quintile of PCS was a strong predictor of all-cause death (hazard ratio (HR) 2.81, 95% CI 1.76, 4.49), incident cancer (HR 1.63, 95% CI 1.10, 2.42), and CHD events (HR 1.99, 95% CI 1.00, 3.96), compared to the highest quintile. (biomedcentral.com)
After controlling for established risk factors, individuals with SCA and asthma had a more than two-fold higher risk of mortality (hazard ratio 2.36, 95% CI 1.21 to 4.62, p =0.01). (haematologica.org)
Proportional hazards models estimated the hazard ratio of hospitalised infections, comparing each biological agent with infliximab. (bmj.com)
We compare hazard ratio estimates for effect of an aggressive treatment regimen from Cox proportional hazards models using time to initial treatment outcome, predicted vital status, and true vital status at the end of the cohort period. (cdc.gov)
Although none of these measures can reliably predict the outcome of individual patients, some measures could be added to the commonly used hazard ratio to provide a more patient-oriented assessment of treatment benefit. (medscape.com)
Regression model2
Recently goodness-of-fit tests have been proposed for checking the proportional subdistribution hazards assumptions in the Fine and Gray regression model. (bvsalud.org)
Time-to-event data were analysed using a Cox proportional-hazards regression model and adjusted for minimisation variables. (uni-muenchen.de)
Ratios6
We used multivariable Cox regression to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for tertiles, and one-standard deviation (SD) unit increments of PA exposures in relation to cancer incidence. (nature.com)
Cox regression was used to estimate hazard ratios of exposure to secondhand smoke compared with having no smoker in the family after propensity score adjustment for clinical and lifestyle characteristics. (bmj.com)
The propensity score adjusted hazard ratios of the two exposure groups compared with having no smoker in the family were 1.46 (95% confidence interval 1.40 to 1.52) and 2.14 (1.99 to 2.29), respectively. (bmj.com)
Cox regression analysis was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) after adjusting for age, sex, frequency of visits to physicians and presence of comorbidities. (cmaj.ca)
The were col ected during the first 2 weeks of February hazard ratios (HRs) for recovery were estimated using a ( Table 1 ). (who.int)
Goodness-of-fit test for monotone proportional subdistribution hazards assumptions based on weighted residuals. (bvsalud.org)
In particular, it is demonstrated that weighted residuals tests using monotone weight functions of time are consistent against monotone proportional subdistribution hazards assumptions. (bvsalud.org)
Results from simulation studies show that weighted residuals tests using monotone random weight functions commonly used in non-proportional hazards regression settings tend to be more powerful for detecting monotone departures than other goodness-of-fit tests assuming no specific time -varying effect or misspecified time -varying effects. (bvsalud.org)
Additional y, most specimens were col ected shared frailty model, which is an extension of the Cox from cases in Cebu province, including from the independ- proportional hazards model that accounts for clustering, ent cities of Cebu City, Lapu-Lapu City and Mandaue City and the proportional hazards assumption was checked (191 [60.3%] of specimens overall and 48/68 [70.6%] using Schoenfeld residuals. (who.int)
Models7
Recurring event or repeated event models relax that assumption. (wikipedia.org)
Significant associations between childhood energy intake and cancer mortality were seen when the confounding effects of social variables were taken into account in proportional hazards models (relative hazard for all cancer mortality 1.15 (95% confidence interval 1.06 to 1.24), P=0.001, for every MJ increase in adult equivalent daily intake in fully adjusted models). (bmj.com)
Cox proportional hazards models, adjusted for age and state, were used to estimate associations between ESRD and: (1) ordinal categories of intensity-weighted lifetime use of 39 pesticides, (2) poisoning and high-level pesticide exposures and (3) pesticide exposure resulting in a medical visit or hospitalisation. (bmj.com)
Cox proportional hazard models were used to explore the associations between quintiles of physical and mental component summary score (PCS and MCS respectively) of the SF-12 and adverse outcomes. (biomedcentral.com)
Multivariate Cox proportional hazard models were used to estimate improvements in CML survival associated with the introduction of first-line imatinib therapy. (ajmc.com)
All models, however, have assumptions and uncertainties and may not accurately represent actual environmental conditions. (cdc.gov)
Violates2
Do I need to care if an adjustment variable violates the proportional hazards assumption? (stackexchange.com)
This makes it possible to identify the cross-sectional unit that violates the homogeneity assumption in case the null hypothesis of equal parameters is rejected. (lu.se)
Discrete-time2
More specifically, the choice of hazard specification in the discrete-time framework is motivated by the asymptotic distribution of threshold excesses of a continuous duration variable. (lu.se)
Since the cloglog model is the discrete-time analogue of the Cox model, the Pareto model can be used to test the proportional hazards assumption imposed by the Cox model, even when duration times are coarsely grouped. (lu.se)
Model10
I'm running a cause-specific Cox proportional hazard model to identify the association between potential risk factors and an outcome in a cohort study. (stackexchange.com)
Birth year was included as a stratification factor in the Cox model, but no other covariable violated the proportional hazard assumption. (bmj.com)
A Cox proportional hazard model was used to assess whether adequate folate supplementation was associated with early (i.e. (medicaljournals.se)
The proportional-hazard assumption for the Cox model was checked graphically. (medicaljournals.se)
This may violate the non-informative censoring assumption of the model and may produce biased effect estimates. (cdc.gov)
Conclusions: Although studies often use initial treatment outcomes to estimate treatment effects, this may violate the non-informative censoring assumption of the Cox proportional hazards model and result in biased treatment effect estimates. (cdc.gov)
Chapter 2 introduces a novel hazard rate model that is much more flexible with respect to the imposed covariate effects than the conventional cloglog, logit, and probit specifications. (lu.se)
In fact, the proposed Pareto hazard model incorporates the most commonly used cloglog and logit specifications as special cases. (lu.se)
Finally, the fact that the Pareto hazard model nests the cloglog as a special case entails an additional advantage. (lu.se)
A Cox proportional hazard model was used to estimate risk of subsequent malignancies in NMSC patients versus controls and to assess the potential confounding effects of multiple risk factors on this risk. (cdc.gov)
Interpretation1
The aim of this course is to enable students to analyse data from studies in which individuals are followed up until a particular event occurs - e.g. death, cure, relapse - making use of follow-up data for those who do not experience the event,with proper attention to underlying assumptions and a major emphasis on the practical interpretation and communication of results. (edu.au)
Time1
Loss-adjusted survival is estimated under the assumption that survival of patients lost to follow-up is the same as that for patients with known follow-up time and similar characteristics of different prognostic factors at first entry. (who.int)
Relation1
The WAI index is based on the assumption of a combination of human resources in relation to social, mental and physical demands, as well as its relationship to management, organizational culture, community and the workplace 8 . (bvsalud.org)
Assessment1
The purpose of this document is to provide an overview of the modes of transmission of human immunodeficiency virus (HIV) in the workplace, an assessment of the risk of transmission under various assumptions, principles underlying the control of risk, and specific risk-control recommendations for employers and workers. (cdc.gov)
Leads1
Inverse sampling weights in Cox proportional hazard leads to violation of the PH-assumption? (stackexchange.com)
Cancer2
RÉSUMÉ Le cancer du sein est un problème de santé publique en République islamique d'Iran. (who.int)
Le jeu de données sur le cancer du sein incluait 1574 femmes diagnostiquées avec un cancer du sein entre 2002 et 2012 inscrites au Registre du Cancer de la Province de Fars, en République islamique d'Iran. (who.int)
Regression models2
Cox proportional hazards regression models were used to estimate relative risks (RR) with 95% CIs, adjusted for potential confounders. (bmj.com)
Multivariable Cox proportional hazards and piece-wise Cox regression models were used to examine the associations. (nih.gov)
Marginalizing conditional survival models can violate the proportional hazards assumption for some frailty distributions, disrupting the connection to a conditional model. (nih.gov)
Methods: The Kaplan-Meier method was used to evaluate the survival curves of each variable, then Cox-Proportional Hazards model determined the risk of cervical cancer-specific death in relation to each variable. (sdsu.edu)
For survival data with measurement error in covariates, there has been extensive discussion in the literature with the focus typically centered on proportional hazards models. (jstatsoft.org)
Dose-related trends are identified with Tarone's life table test, and dose-related effects on survival are assessed using a Cox proportional hazards model. (nih.gov)
Cox's2
Cox's proportional hazards model was employed to determine the hazard of mortality associated with a specific fracture for a given risk profile, and the hazard was then transformed into YLL using the Gompertz law of mortality. (elifesciences.org)
In this presentation, the binomial frailty model derived upon the Cox's proportional hazard assumption and the binomial distribution of gene alleles is introduced. (mpg.de)
Mortality2
Independent predictors of mortality were determined using Cox proportional-hazards analysis to identify subgroups with distinct disease behaviour. (ersjournals.com)
Mortality risk was assessed using Cox proportional hazards, adjusting for sociodemographic and lifestyle factors, health conditions and influenza and pneumococcal vaccination status. (bmj.com)
Kaplan-Meier1
Also, if modeling categorical variables, you could create Kaplan-Meier curves for each variables and see if they are roughly proportional to each other. (stackexchange.com)
Baseline hazard1
A Two-step MLE has also been introduced, to obtain a non-parametric form of the baseline hazard function. (mpg.de)
Covariate1
Protection provided by vaccination (analyzed as a time-dependent covariate) was evaluated using Cox proportional hazards regression, with change in dominant circulating lineages over time accounted for by time-dependent coefficients. (medrxiv.org)
Theoretical1
This method has theoretical advantages such as robustness to distributional assumptions for error prone covariates. (jstatsoft.org)
Outcome1
In essence, the hazard for the composite outcome was 80% lower among the vaccinated relative to those who were unvaccinated in the same study. (wikipedia.org)
Statistical1
Background: During trials that span decades, new evidence including progress in statistical methodology, may require revision of original assumptions. (lse.ac.uk)
Results3
The aim of this course is to enable students to analyse data from studies in which individuals are followed up until a particular event occurs - e.g. death, cure, relapse - making use of follow-up data for those who do not experience the event, with proper attention to underlying assumptions and a major emphasis on the practical interpretation and communication of results. (edu.au)
The gsDesign package is used as a check for results under proportional hazards as well as a source from deriving bounds using spending functions. (r-project.org)
The estimation has been done incorporating various assumptions on the genetic and heterogeneity parameters so that the results presented represent a range from normal to extreme situations. (mpg.de)
Rate1
Under the above enrollment, failure and dropout rate assumptions we now derive sample size for a trial targeted to complete in 36 months with no interim analysis, \(90\%\) power and \(2.5\%\) Type I error. (r-project.org)
Check1
In my previous question I'm trying to deal with the problem that you have after testing the PH assumption but the top part shows how you check by using Grambsch and Therneau's method. (stackexchange.com)
Evidence1
If you have evidence of non-proportional hazards, don't despair. (theanalysisfactor.com)
Means1
I want a means to assess whether the PH assumption is true. (stackexchange.com)