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An objective method for measurement of sedentary behavior in 3- to 4-year olds
John J Reilly1, Jennifer Coyle, Louise Kelly
1Division of Developmental Medicine and. Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow, Scotland. jjr2y@clinmed.gla.ac.uk
Insights
Accelerometry accurately measures sedentary behavior in young children. This objective method aids in understanding and addressing childhood obesity by quantifying physical activity levels.
Area of Science:
- Pediatric health
- Physical activity measurement
- Childhood obesity research
Background:
- Sedentary behavior is a growing concern in early childhood.
- Objective measurement tools are needed to accurately assess sedentary time in young children.
- Existing methods may not reliably quantify sedentary behavior in preschoolers.
Purpose of the Study:
- To evaluate accelerometry's effectiveness in quantifying sedentary behavior in 3- to 4-year-old children.
- To establish a reliable cut-off point for accelerometry data to define sedentary behavior.
- To validate this accelerometry-based method against direct observation.
Main Methods:
- A validation study developed an accelerometry cut-off using direct observation as the criterion method in 30 children aged 3-4 years.
- The established cut-off was cross-validated in an independent sample of 52 healthy children aged 3-4 years.
- Sensitivity and specificity were calculated to assess the accuracy of the accelerometry cut-off.
Main Results:
- An accelerometry output cut-off of <1100 counts/min demonstrated optimal sensitivity and specificity for detecting sedentary behavior.
- In cross-validation, the cut-off achieved 83% sensitivity, correctly classifying 438 out of 528 inactive minutes.
- Specificity was 82%, correctly classifying 1251 out of 1526 non-inactive minutes.
Conclusions:
- Accelerometry provides an objective and valid method for quantifying sedentary behavior in young children.
- This technique has significant potential for research into the causes, prevention, and treatment of childhood obesity.
- The findings support the use of accelerometry in epidemiological studies and clinical interventions for pediatric obesity.
Objective:
To test the ability of accelerometry to quantify sedentary behavior in 3- to 4-year-old children.
Research Methods And Procedures:
We developed a cut-off for accelerometry output (validation study) in 30 healthy 3 to 4 year olds, which provided highest sensitivity and specificity for the detection of sedentary behavior relative to a criterion method of measurement, direct observation using the children's physical activity form. We then cross-validated the cut-off in an independent sample of healthy 3 to 4 year olds (n = 52).
Results:
In the validation study, optimal sensitivity and specificity for the detection of sedentary behavior were obtained at an accelerometry output cut-off of <1100 counts/min. In the cross-validation, sensitivity was 83%: 438/528 inactive minutes were correctly classified. Specificity was 82%: 1251/1526 noninactive minutes were correctly classified using this cut-off.
Discussion:
Sedentary behavior can be quantified objectively in young children using accelerometry. This new technique could be considered for a wide variety of applications in the etiology, prevention, and treatment of childhood obesity.
