JSM Preliminary Online Program
This is the preliminary program for the 2009 Joint Statistical Meetings in Washington, DC.

The views expressed here are those of the individual authors
and not necessarily those of the ASA or its board, officers, or staff.


Back to main JSM 2009 Program page

View My Program  /  View My Program (condensed)  /  What is My Program?



Activity Number: 269
Type: Contributed
Date/Time: Tuesday, August 4, 2009 : 8:30 AM to 10:20 AM
Sponsor: Section on Risk Analysis
Abstract - #304941
Title: Interpreting Differential Effects in Light of Fundamental Statistical Tendencies
Author(s): James P. Scanlan*+
Companies: James P. Scanlan, Attorney at Law
Address: 1527 30th Street NW, Washington, DC, 20007,
Keywords: subgroup analyses ; differential effects ; interaction ; baseline rates
Abstract:

Subgroup analyses are subject of increasing discussion in epidemiology. Overlooked in the discussions is the statistical basis for expecting interventions to yield different proportionate changes in rates of experiencing an outcome for groups with different baseline rates. This presentation would explain the statistical basis for expecting an intervention that reduces an outcome rate to cause the group with the lower baseline rate to experience a larger proportionate reduction in the outcome while causing the comparison group to experience a larger proportionate increase in experiencing the opposite outcome. It will also address the way that expectation comports with observed patterns of differential effects in individual studies and meta-analyses of subgroup effects and the implications of the expectation for the interpretation of seeming differential effects.


  • The address information is for the authors that have a + after their name.
  • Authors who are presenting talks have a * after their name.

Back to the full JSM 2009 program


JSM 2009 For information, contact jsm@amstat.org or phone (888) 231-3473. If you have questions about the Continuing Education program, please contact the Education Department.
Revised September, 2008