A multilevel approach to examining time-specific effects in accelerometer-assessed physical activity.

ABSTRACT:

Objectives

Popular methods for analyzing accelerometer data often use a single physical activity outcome variable such as average-weekly or total physical activity. These approaches limit the types of research questions that can be answered and fail to utilize the detailed, time-specific information available from accelerometers. This study proposes the use of multilevel modeling, which tested intervention effects at specific time periods.

Design

The motivating example was the Active by Choice Today trial. Simulations were used to test whether the application of time-specific hypotheses about when physical activity intervention treatment effects were expected to occur (e.g., after-school hours) increased power to detect effects compared to traditional methods.

Methods

SUBMITTER: Lawman HG 

PROVIDER: S-EPMC4362866 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature