JSM 2005 - Toronto

Abstract #304476

This is the preliminary program for the 2005 Joint Statistical Meetings in Minneapolis, Minnesota. Currently included in this program is the "technical" program, schedule of invited, topic contributed, regular contributed and poster sessions; Continuing Education courses (August 7-10, 2005); and Committee and Business Meetings. This on-line program will be updated frequently to reflect the most current revisions.

To View the Program:
You may choose to view all activities of the program or just parts of it at any one time. All activities are arranged by date and time.



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


The Program has labeled the meeting rooms with "letters" preceding the name of the room, designating in which facility the room is located:

Minneapolis Convention Center = “MCC” Hilton Minneapolis Hotel = “H” Hyatt Regency Minneapolis = “HY”

Back to main JSM 2005 Program page



Legend: = Applied Session, = Theme Session, = Presenter
Activity Number: 323
Type: Contributed
Date/Time: Tuesday, August 9, 2005 : 2:00 PM to 3:50 PM
Sponsor: Biopharmaceutical Section
Abstract - #304476
Title: Missing Data in Longitudinal Controlled Clinical Trial: A Power Comparison for Intent-to-treat Analysis
Author(s): Hrishikesh Chakraborty*+ and Hong Gu
Companies: RTI International and Dalhousie University
Address: 3040 Cornwallis RD, RTP, NC, 27709, United States
Keywords: longitudinal study ; controlled clinical trials ; missing value ; intent-to-treat analysis ; mixed model ; power
Abstract:

Missing values and dropouts are common issues in all areas of medicine and public health research, and intent-to-treat (ITT) analysis has become a widely accepted method for analysis of clinical trials in the pharmaceutical industry. In most clinical trials, some patients do not complete their intended followup according to the protocol, generating missing values. Missing values lead to concern and confusion in identifying the ITT population and makes data analysis more complex and challenging. There is no adequate strategy for ITT analyses of longitudinal clinical trial data with missing values. Use of ad hoc strategies dealing with missing values for an ITT analysis is common practice of clinical trials. A detailed investigation based on simulation studies was performed to develop recommendations for ITT analysis of longitudinal controlled clinical trial data with missing values. We compared sizes and powers between popular ad hoc approaches and linear mixed model under different missing scenarios. Simulation results suggest that for a high percentage of missing values, mixed model approach without any ad hoc imputation provide more powerful comparison.


  • 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 2005 program

JSM 2005 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 March 2005