Evidence map›Paper›PMID 24664670›Full record

ArticlePharmacoepidemiology and drug safety2014

Using fractional polynomials to model the effect of cumulative duration of exposure on outcomes: applications to cohort and nested case-control designs.

Peter C Austin, Laura Y Park-Wyllie, David N Juurlink

Abstract read
In one paragraph

Article in Pharmacoepidemiology and drug safety, 2014. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 5 papers.

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0cells of the map it votes in
5citing papers in PubMed
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1 · What the graph read from it

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3 · Its place in the literature

Who cites it

5 citing papers in PubMed.

  1. Optimal designs for health risk assessments using fractional polynomial models.Stochastic environmental research and risk assessment : research journal · 2022
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4 · The record

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5 · Who and what money

Authors and funding

3 authors.

Peter C AustinInstitute for Clinical Evaluative Sciences, Toronto, Ontario, Canada; Institute of Health Management, Policy and Evaluation, University of Toronto, Toronto, Ontario, Canada; Schulich Heart Research Program, Sunnybrook Research Institute, Toronto, Canada.
Laura Y Park-Wyllie
David N Juurlink

Funding

Canadian Institutes of Health Research MOP 86508
6 · The paper itself

Abstract

purposeDetermining the nature of the relationship between cumulative duration of exposure to an agent and the hazard of an adverse outcome is an important issue in environmental and occupational epidemiology, public health and clinical medicine. The Cox proportional hazards regression model can incorporate time-dependent covariates. An important class of continuous time-dependent covariates is that denoting cumulative duration of exposure.

methodsWe used fractional polynomial methods to describe the association between cumulative duration of exposure and adverse outcomes. We applied these methods in a cohort study to examine the relationship between cumulative duration of use of the antiarrhythmic drug amiodarone and the risk of thyroid dysfunction. We also used these methods with a conditional logistic regression model in a nested case-control study to examine the relationship between cumulative duration of use of bisphosphonate medication and the risk of atypical femur fracture.

resultsUsing a cohort design and a Cox proportional hazards model, we found a non-linear relationship between cumulative duration of use of the antiarrhythmic drug amiodarone and the risk of thyroid dysfunction. The risk initially increased rapidly with increasing cumulative use. However, as cumulative duration of use increased, the rate of increase in risk attenuated and eventually levelled off. Using a nested case-control design and a conditional logistic regression model, we found evidence of a linear relationship between duration of use of bisphosphonate medication and risk of atypical femur fractures.

conclusionsFractional polynomials allow one to model the relationship between cumulative duration of medication use and adverse outcomes.

Indexed as

Models, StatisticalProportional Hazards ModelsAgedAmiodaroneAnti-Arrhythmia AgentsCase-Control StudiesCohort StudiesDiphosphonatesEpidemiologic Research DesignFemaleFemurFractures, BoneHumansLogistic ModelsMaleNonlinear DynamicsAmiodaroneAnti-Arrhythmia AgentsDiphosphonatescohort studyCox proportional hazards regression modelfractional polynomialsnested case-control studypharmacoepidemiologysurvival analysistime-dependent covariates

Identifiers

PMID24664670
PMCPMC4230473

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.