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Related Experiment Video

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Visualization of Intensity Levels to Reduce the Gap Between Self-Reported and Directly Measured Physical Activity

Visualization of Intensity Levels to Reduce the Gap Between Self-Reported and Directly Measured Physical Activity

Published on: March 7, 2019

Non-response bias in physical activity trend estimates.

Cora L Craig¹, Christine Cameron, Joe Griffiths

¹Canadian Fitness and Lifestyle Research Institute, Ottawa, Canada. ccraig@cflri.ca

BMC Public Health

|November 26, 2009

Summary

This study found that changes in survey response rates did not significantly impact physical activity (PA) trends in Canadian adults. Understanding potential biases is crucial for accurate health policy decisions regarding energy balance.

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Area of Science:

Public Health
Epidemiology
Behavioral Science

Background:

Reported increases in leisure time physical activity (PA) and obesity present a paradox.
Differential bias in PA estimates over time is a potential explanation for these trends.

Purpose of the Study:

To investigate the impact of changing response rates on PA prevalence estimates in Canadian adults.
To assess potential biases in PA data collection methods.

Main Methods:

Analysis of national telephone surveys on PA conducted between 1995 and 2007.
Comparison of PA prevalence between survey participants and hard-to-reach individuals using adjusted t tests.

Main Results:

An increase in the number of calls needed to reach households and initial refusal rates was observed.
Higher PA prevalence was noted with more contact attempts, but this finding lacked statistical significance after adjustments.

Conclusions:

Differential non-response rates did not significantly alter physical activity trend estimates.
Awareness of potential biases is vital for health policymakers analyzing energy balance trends.