Validating Machine -Learned Classifiers of Sedentary Behavior and Physical Activity (iWatch)
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ClinicalTrials.gov Identifier: NCT01775826 |
Recruitment Status
:
Completed
First Posted
: January 25, 2013
Last Update Posted
: May 13, 2016
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Condition or disease |
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Physical Activity Sedentary Lifestyle |
Study Type : | Observational |
Actual Enrollment : | 225 participants |
Observational Model: | Cohort |
Time Perspective: | Cross-Sectional |
Official Title: | Validating Machine -Learned Classifiers of Sedentary Behavior and Physical Activity |
Study Start Date : | March 2013 |
Actual Primary Completion Date : | April 2016 |
Actual Study Completion Date : | April 2016 |

Group/Cohort |
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Child and adolescent
6-17 years of age
|
Adult
18-55 years of age
|
Older adults
65-85 years of age
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- physical activity behavior classification using study sensors (accelerometers, Sensecam and GPS) [ Time Frame: Baseline ]
Using an annotated data set of SenseCam images in three free-living population subgroups, we will compare sensitivity, specificity and percent agreement between behavioral classifiers derived from: (a) single axis vs. multi axis accelerometers; (b) aggregated movement counts vs. raw acceleration data; (c) hip vs. wrist mounted accelerometers.
Determine (a) the extent to which adding GPS data improves discrimination accuracy over accelerometer only behavior classification (i.e., best classifier resulting from Aim 1); and (b) the extent to which adding GIS data improves discrimination accuracy over accelerometer and GPS behavior classification alone (i.e., best classifier resulting from Aim 2a).

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Ages Eligible for Study: | 6 Years to 85 Years (Child, Adult, Senior) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | Yes |
Sampling Method: | Non-Probability Sample |
Inclusion Criteria:
Inclusion Criteria for participants 6-17 yr olds:
- provide written parental consent to complete study protocols;
- provide verbal assent to complete study protocols;
- willingness to complete 2 visits to UCSD offices;
- willingness to wear multiple sensor devices on 7 days for 12 hours per day;
- willingness to wear wrist accelerometer on 7 days for 24 hours per day;
- willingness to have their height and weight measured;
- be able to walk unassisted
- able to read and understand study materials in English.
Inclusion Criteria for participants 18-55 yr old:
- provide written consent to complete study protocols;
- willingness to complete 2 visits to UCSD offices;
- willingness to wear multiple sensor devices on 7 days for 12 hours per day;
- willingness to wear wrist accelerometer on 7 days for 24 hours per day;
- complete a survey assessing their demographic characteristics;
- willingness to have their height and weight measured;
- be physically and cognitively able to walk unassisted,
- able to read and understand study materials in English.
Inclusion Criteria for participants 65-85 yr olds:
- provide written consent to complete study protocols;
- correctly answer verbal questions about their comprehension of the informed consent;
- willingness to complete 2 visits to UCSD offices;
- willingness to wear multiple sensor devices on 7 days for 12 hours per day;
- willingness to wear wrist accelerometer on 7 days for 24 hours per day;
- complete a survey assessing their demographic;
- willingness to have their height and weight measured;
- be physically and cognitively able to walk without the assistance of another person (walking aids are permitted)
- able to read and understand study materials in English.
Exclusion Criteria:
- unable to ambulate;
- attends a workplace or school on monitoring days that prohibits static images being taken by a SenseCam worn around the neck of the participant;
- pregnancy in second or third trimester.

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01775826
United States, California | |
UCSD | |
La Jolla, California, United States, 92093 |
Publications:
Responsible Party: | Jacqueline Kerr, Assistant Professor, University of California, San Diego |
ClinicalTrials.gov Identifier: | NCT01775826 History of Changes |
Other Study ID Numbers: |
1R01CA164993-01A1 ( U.S. NIH Grant/Contract ) |
First Posted: | January 25, 2013 Key Record Dates |
Last Update Posted: | May 13, 2016 |
Last Verified: | May 2016 |
Keywords provided by Jacqueline Kerr, University of California, San Diego:
physical activity sedentary behavior accelerometer |
GPS GIS machine learning |