New Findings Reported from Exponent Describe Advances in Risk Management (An Assessment of the Cox Proportional Hazards Regression Model for…

New Findings Reported from Exponent Describe Advances in Risk Management (An Assessment of the Cox Proportional Hazards Regression Model for Epidemiologic Studies)

By a News Reporter-Staff News Editor at Insurance Weekly News -- A new study on Risk Management is now available. According to news reporting out of Bellevue, Washington, by VerticalNews editors, research stated, "The basic assumptions of the Cox proportional hazards regression model are rarely questioned. This study addresses whether hazard ratio, i.e., relative risk (RR), estimates using the Cox model are biased when these assumptions are violated."

Financial support for this research came from American Petroleum Institute.

Our news journalists obtained a quote from the research from Exponent, "We investigated also the dependence of RR estimates on temporal exposure characteristics, and how inadequate control for a strong, time-dependent confounder affects RRs for a modest, correlated risk factor. In a realistic cohort of 500,000 adults constructed using the National Cancer Institute Smoking History Generator, we used the Cox model with increasing control of smoking to examine the impact on RRs for smoking and a correlated covariate X. The smoking-associated RR was strongly modified by age. Pack-years of smoking did not sufficiently control for its effects; simultaneous control for effect modification by age and time-dependent cumulative exposure, exposure duration, and time since cessation improved model fit. Even then, residual confounding was evident in RR estimates for covariate X, for which spurious RRs ranged from 0.980 to 1.017 per unit increase. Use of the Cox model to control for a time-dependent strong risk factor yields unreliable RR estimates unless detailed, time-varying information is incorporated in analyses."

According to the news editors, the research concluded: "Notwithstanding, residual confounding may bias estimated RRs for a modest risk factor."

For more information on this research see: An Assessment of the Cox Proportional Hazards Regression Model for Epidemiologic Studies. Risk Analysis, 2017;():. (Wiley-Blackwell - www.wiley.com/; Risk Analysis - onlinelibrary.wiley.com/journal/10.1111/(ISSN)1539-6924)

Our news journalists report that additional information may be obtained by contacting S.H. Moolgavkar, Center for Health Sciences, Exponent Inc, Bellevue, WA and Menlo Park, CA, United States. Additional authors for this research include E.T. Chang, H.N. Watson and E.C Lau.

The direct object identifier (DOI) for that additional information is: https://doi.org/10.1111/risa.12865. This DOI is a link to an online electronic document that is either free or for purchase, and can be your direct source for a journal article and its citation.

Keywords for this news article include: Bellevue, Washington, United States, Risk Management, Risk and Prevention, North and Central America.

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