Title page for ETD etd-121499-141337

Document Type thesis

Author Name Delcroix, Sophie M.

Email Address sophiedelcroix at hotmail.com

URN etd-121499-141337

Title Bayesian Analysis of Cancer Mortality Rates from Different Types and their Relative Occurrences

Degree MS

Department Mathematical Sciences

Advisors
Balgobin Nandram, Advisor
Hyunjoong Kim, Co-Advisor
Homer Walker, Department Head

Keywords
Bayesian method
mapping

Date of Presentation/Defense 1999-12-06

Availability unrestricted

Abstract
We analyze mortality data from prostate, colon, lung, and
all other types (called other cancer) to obtain age specific and age
adjusted mortality rates for white males in the U.S. A related problem
is to estimate the relative occurrences of these four
types of cancer. We use Bayesian method because it permits a degree of smoothing which is needed to analyze data at a small area level and to assess the patterns.

In the recent Atlas of the United States Mortality (1996) each
type of cancer was analyzed individually. The difficulty in doing so
is that there are many small areas with zero deaths. We conjecture that simultaneous analyses might help to overcome this problem, and at the same time to estimate the relative occurrences.

We start with a Poisson model for the deaths, which produces a
likelihood function that separates into two parts: a Poisson likelihood
for the rates and a multinomial likelihood for the relative occurrences. These permit the
use of a standard Poisson regression model on age as in Nandram,
Sedransk and Pickle (1999), and the novelty is a multivariate logit
model on the relative occurrences in which per capita income,
the percent of people below poverty level, education (percent
of people with four years of college) and two criteria pollutants,
EPAPM25 and EPASO2, are used as covariates.

We fitted the models using Markov chain Monte Carlo methods.
We used one of the models to present maps of occurrences and
rates for the four types. An alternative model did not work well
because it provides the same pattern by age and disease.

We found that while EPAPM25 has a negative effect on the
occurrences, EPASO2 has a positive effect. Also, we found some
interesting patterns associated with the geographical variations of mortality rates and the relative occurrences of the four cancer types.

Files
delcroix.pdf

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Document Type	thesis
Author Name	Delcroix, Sophie M.
Email Address	sophiedelcroix at hotmail.com
URN	etd-121499-141337
Title	Bayesian Analysis of Cancer Mortality Rates from Different Types and their Relative Occurrences
Degree	MS
Department	Mathematical Sciences
Advisors	Balgobin Nandram, Advisor Hyunjoong Kim, Co-Advisor Homer Walker, Department Head
Keywords	Bayesian method mapping
Date of Presentation/Defense	1999-12-06
Availability	unrestricted
Abstract We analyze mortality data from prostate, colon, lung, and all other types (called other cancer) to obtain age specific and age adjusted mortality rates for white males in the U.S. A related problem is to estimate the relative occurrences of these four types of cancer. We use Bayesian method because it permits a degree of smoothing which is needed to analyze data at a small area level and to assess the patterns. In the recent Atlas of the United States Mortality (1996) each type of cancer was analyzed individually. The difficulty in doing so is that there are many small areas with zero deaths. We conjecture that simultaneous analyses might help to overcome this problem, and at the same time to estimate the relative occurrences. We start with a Poisson model for the deaths, which produces a likelihood function that separates into two parts: a Poisson likelihood for the rates and a multinomial likelihood for the relative occurrences. These permit the use of a standard Poisson regression model on age as in Nandram, Sedransk and Pickle (1999), and the novelty is a multivariate logit model on the relative occurrences in which per capita income, the percent of people below poverty level, education (percent of people with four years of college) and two criteria pollutants, EPAPM25 and EPASO2, are used as covariates. We fitted the models using Markov chain Monte Carlo methods. We used one of the models to present maps of occurrences and rates for the four types. An alternative model did not work well because it provides the same pattern by age and disease. We found that while EPAPM25 has a negative effect on the occurrences, EPASO2 has a positive effect. Also, we found some interesting patterns associated with the geographical variations of mortality rates and the relative occurrences of the four cancer types.
Files	delcroix.pdf