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Assessing the Accuracy of Fitness Smartwatch Data for Cardiovascular and Physical Activity Monitoring: A Validation Study in Digital Health
Published on: February 21, 2025
Reliability and validity testing of a single-item physical activity measure
1British Heart Foundation National Centre for Physical Activity and Health, School of Sport, Exercise and Health Sciences, Loughborough University, Leicestershire LE11 3TU, UK. k.milton@lboro.ac.uk
British Journal of Sports Medicine
|May 21, 2010
Summary
A new single-item physical activity screening tool was developed and tested. Both past-week and past-month versions showed good reliability and validity for assessing eligibility for behavior change interventions.
Area of Science:
- Public Health
- Exercise Science
- Behavioral Medicine
Background:
- Accurate physical activity assessment is crucial for public health interventions.
- Existing tools can be lengthy, posing barriers to widespread use.
- There is a need for brief, reliable screening tools to identify individuals for behavior change programs.
Purpose of the Study:
- To develop and validate a novel single-item tool for screening physical activity.
- To assess the tool's suitability for determining eligibility for behavior change interventions.
Main Methods:
- Two single-item tools were created, using past-week and past-month recall periods.
- 480 adults were recruited across England, Scotland, and Wales using quota sampling.
- Test-retest reliability and concurrent validity (vs. Global Physical Activity Questionnaire and UK Active People Survey) were assessed via telephone interviews.
Main Results:
- Both single-item tools demonstrated strong reproducibility (Spearman's r = 0.72-0.82).
- The past-week version showed good agreement in classifying individuals meeting physical activity recommendations (kappa=0.63).
- Concurrent validity was modest, with the past-week version showing stronger correlation (r=0.53) compared to the past-month version (r=0.33-0.48).
Conclusions:
- The developed single-item physical activity measures exhibit comparable reliability and concurrent validity to existing short tools.
- Further research is recommended to establish criterion validity against objectively measured activity and assess responsiveness to change for program evaluation.
