Document Detail


Age-dependent U-shaped risk functions and Aalen's additive risk model.
MedLine Citation:
PMID:  9750247     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Epidemiologic studies of time to some failure often show a quadratic relation between the risk of failure and covariate(s). We study the nadir for a given covariate, i.e., the value of the covariate associated with the lowest risk (supposing a U-shape), within Aalen's additive risk model. This model was applied since the effect of the covariate(s) is allowed to vary over time and, as a consequence, a given nadir can vary over time. We propose a test for the null hypothesis that the nadir is time independent and, if this is the case, an estimate of the nadir. Large sample properties of the test statistic and estimator are derived. The methods are illustrated with data where time to death is related to body mass index.
Authors:
T Martinussen; T I Sørensen
Related Documents :
8800607 - A sas macro for stepwise correlated binary regression.
10877317 - Graphical exploration of covariate effects on survival data through nonparametric quant...
8700047 - A comparison of standing steadiness measurements from two devices: covariates and norma...
12116437 - Use of two-block partial least-squares to study covariation in shape.
8190827 - Intrinsic and extrinsic factors affect infant responses to maternal separation.
10396807 - Quantification of paracetamol in intact tablets using near-infrared transmittance spect...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Biometrics     Volume:  54     ISSN:  0006-341X     ISO Abbreviation:  Biometrics     Publication Date:  1998 Sep 
Date Detail:
Created Date:  1998-11-03     Completed Date:  1998-11-03     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0370625     Medline TA:  Biometrics     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  989-1001     Citation Subset:  IM    
Affiliation:
Department of Biostatistics, University of Copenhagen, Denmark. torbenm@dina.kvl.dk
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Adult
Age Factors
Aged
Aged, 80 and over
Biometry / methods*
Body Mass Index
Epidemiologic Factors
Humans
Middle Aged
Models, Statistical*
Obesity / mortality,  pathology
Proportional Hazards Models
Risk*
Risk Factors

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Estimating a treatment effect from multidimensional longitudinal data.
Next Document:  Estimating equations with incomplete categorical covariates in the Cox model.