The name is absent



Chapter 4

Borrowing Strength with

Hierarchical Models over

Non-Exchangeable Subpopulations

4.1 Outline

We address statistical inference in a phase II trial of sarcoma. Sarcoma is a rare can-
cer affecting connective and soft tissues (e.g., cartilage and fat). Sarcoma is a very
heterogeneous disease with many different subtypes with widely different prognosis.
In the proposed design we pay particular attention to the heterogeneous nature of the
disease and the fact that different disease subtypes are related but can not be con-
sidered
a priori exchangeable. We classify different subtypes by the overall prognosis
as poor, intermediate or good. The objective of the study is to assess the efficacy
of a new drug in patients with different subtypes of sarcoma. Let
pi, i = 1,... ,n,
denote the probability of response (defined below) for a patient with disease subtype
i. One possible approach is to analyze the different subtypes as separate studies.
But due to the rare nature of some of the subtypes the enrollment in
n — 12 sepa-
rate studies would be way too slow. This leads us to consider borrowing of strength

81



More intriguing information

1. A Theoretical Growth Model for Ireland
2. 03-01 "Read My Lips: More New Tax Cuts - The Distributional Impacts of Repealing Dividend Taxation"
3. Internationalization of Universities as Internationalization of Bildung
4. The name is absent
5. Three Strikes and You.re Out: Reply to Cooper and Willis
6. Has Competition in the Japanese Banking Sector Improved?
7. Epistemology and conceptual resources for the development of learning technologies
8. The name is absent
9. The purpose of this paper is to report on the 2008 inaugural Equal Opportunities Conference held at the University of East Anglia, Norwich
10. Evaluation of the Development Potential of Russian Cities