The objective of this project is to develop new statistical designs and methods to better evaluate partially controlled studies in public health. There are three specific aims.
The first aim i s to develop methods to evaluate treatments in studies that: do not directly control which subjects get which treatment, or which subjects provide outcomes; but do control the location of the sites that provide the treatments. Because existing methods, including standard instrumental variables, cannot handle the coexistence of the uncontrolled factors of taking treatment and of providing outcomes, the work under aim 1 is essential for proper treatment evaluation. This work will be applied to ongoing needle exchange programs in Baltimore, for preventing HIV transmission.
The second aim i s to develop new methods for clinical trials where treatment received is controlled, and outcomes are measured; a post-treatment surrogate endpoint is measured; and the goal is to estimate the treatments effects on the outcome that are concurrent and not concurrent with the surrogate. The methods under aim 2 use a new type of stratification for the uncontrolled surrogates that avoid the complications of standard stratifications on post-treatment variables. This work is essential for proper evaluation of early post-treatment symptoms as measures of later treatment effect, and we will apply it to cancer and ophthalmology trials.
The third aim i s to develop methods for study designs where: some persons drop out of a longitudinal follow-up, and where we can find (double-sample) a representative subset of the dropouts. This work is essential for preserving generalizability of results from long follow-up studies, and we will apply it to better evaluate time to potential drug dependence in youths.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
5R01EY014314-02
Application #
6623250
Study Section
Special Emphasis Panel (ZRG1-SNEM-5 (01))
Program Officer
Kurinij, Natalie
Project Start
2002-05-01
Project End
2006-04-30
Budget Start
2003-05-01
Budget End
2004-04-30
Support Year
2
Fiscal Year
2003
Total Cost
$240,338
Indirect Cost
Name
Johns Hopkins University
Department
Biostatistics & Other Math Sci
Type
Schools of Public Health
DUNS #
001910777
City
Baltimore
State
MD
Country
United States
Zip Code
21218
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