|
Activity Number:
|
151
|
|
Type:
|
Contributed
|
|
Date/Time:
|
Monday, July 30, 2007 : 10:30 AM to 12:20 PM
|
|
Sponsor:
|
Section on Statistics in Epidemiology
|
| Abstract - #309926 |
|
Title:
|
A Method To Assess Bias Reduction in Observational Studies of Influenza Vaccine Effectiveness
|
|
Author(s):
|
Jennifer Nelson*+ and Michael Jackson and Noel Weiss and Lisa Jackson
|
|
Companies:
|
Group Health Center for Health Studies and Group Health Center for Health Studies and University of Washington and Group Health Center for Health Studies
|
|
Address:
|
University of Washington, Seattle, WA, 98101,
|
|
Keywords:
|
bias reduction ; observational study ; influenza ; vaccine effectiveness
|
|
Abstract:
|
Accurately estimating the public health benefit of influenza vaccination for seniors is important for planning during pandemic and nonpandemic periods. Existing estimates of vaccine benefit in the elderly are primarily derived from observational studies. These studies typically use data from research or health care utilization databases and consistently report substantial reductions in all-cause mortality and respiratory disease hospitalization risk during influenza season in vaccinated seniors. However, there are reasons to believe that bias due to differences between vaccinated and unvaccinated seniors may account for some or all of these differences. We summarize the evidence for bias in published studies, propose design and analysis strategies that may yield more accurate estimation, and present a novel method to assess the ability of such strategies to reduce bias in future studies.
|
