Survey Design for Studies of Measurement Error in Physical Activity Assessments

• Activity Number: 207
• Type: Contributed
• Date/Time: Monday, July 30, 2007 : 2:00 PM to 3:50 PM
• Sponsor: Section on Survey Research Methods
• Author(s): Nicholas Beyler*+ and Sarah M. Nusser and Wayne Fuller and Alicia Carriquiry
• Companies: Iowa State University and Iowa State University and Iowa State University and Iowa State University
• Keywords: Calibration ; Measurement Error ; Physical Activity ; Energy Expenditure

Abstract

It is widely accepted that energy expenditure (EE) data obtained from 24-hour physical activity (PA) recalls and objective activity sensing devices are subject to considerable measurement error, but limited information is available about the sources and form of the measurement errors. We consider the problem of developing a sample design for a PA survey that includes 24-hour recalls and measurements from an objective sensing device. Our goal is to investigate measurement error models and calibration functions for EE. We propose a measurement model for both types of EE measurements, derive method of moments estimators of model parameters, and use data from a pilot study (Calabro 2006) to calculate preliminary estimates. Finally, we consider the cost structure of the different measurements in determining appropriate sample designs.