Missing Data Handling for Daily Diary Data with Application to Asthma Symptoms eDiary

• Activity Number: 122
• Type: Topic Contributed
• Date/Time: Monday, August 5, 2013 : 8:30 AM to 10:20 AM
• Sponsor: Biometrics Section
• Author(s): Nan Zhang*+ and Yun Chon and Jia Cao and Trina Patel
• Companies: Amgen and Amgen Inc. and Amgen Inc and UCLA
• Keywords: missing data ; Diary Data ; asthma

Abstract

In many clinical trials, subjects' daily diary is used to record everyday symptoms and quality of life. The frequency of missing individual responses is quite high given the nature of daily frequency and burden. This leads to even higher missing in analysis of the derived composite score. In this paper, several missing data handling procedures are explored and a simulation study is conducted to assess the performance of each method under different mechanisms of diary missingness. The results of the simulation study are evaluated in terms of bias in the estimation of treatment difference and power to detect the difference. The symptom eDiary data from an asthma clinical trial is used to model all simulated data to reflect the real world.