IJPAM: Volume 46, No. 4 (2008)
THE PROPORTIONAL HAZARD REGRESSION MODEL
Department of Mathematics
University of the Pacific
Stockton, CA 95211, USA
e-mail: mbhattac@pacific.edu
Abstract.Graft versus host disease (GVHD) is a complication that often arises after
allogeneic bone marrow transplantations. There are two types of GVHD - acute
and chronic. Using a proportional hazard regression model and data obtained
from the international bone marrow transplant registry, we investigate the
risks of the two diseases. We do so by comparing the hazard of death of a
group of patients having one or both of the two diseases to the hazard of
death of a control group of patients who do not have either of the two
diseases. For the analysis involving chronic GVHD, we compare the results of
the proportional hazard model to the results of a simple two population
proportion hypothesis test problem and show how the conclusions differ in the
two situations. Along the way we point out certain interesting aspects of the
data, a few of which contradict some of the commonly believed notions about
the two diseases.
Received: June 13, 2008
AMS Subject Classification: 62A00
Key Words and Phrases: hazard, survival, risk, censored, proportional, transplants
Source: International Journal of Pure and Applied Mathematics
ISSN: 1311-8080
Year: 2008
Volume: 46
Issue: 4