There is a need for a self-report instrument, with sound psychometric properties, for monitoring compliance with physical activity guidelines in youth. This study aimed to develop such an instrument by applying Item Response Theory as well as traditional methods for assessing validity and reliability. Focus groups, conducted with 162 middle school ...
Introduction: To avoid counting movement artifacts as steps, some activity monitors require several consecutive seconds of stepping before steps are retroactively counted towards the total step accumulation. Purpose: To study how algorithms in different activity monitors affect the number of steps recorded during brief, intermittent walking bouts when the walking ...
Purpose: The proposed symposium will introduce novel and intuitive statistical methods for modeling the human circadian rhythm based on data collected using body-worn physical activity monitors. All methods are motivated by and applied to large observational studies. Rationale: Biological rhythms have been under intense methodological development across all disciplines of ...
Sleep disorders occur in around 20% of the population and are associated with a multitude of serious health implications. Whilst polysomnography is considered the 'gold standard' in assessing sleep patterns, it is intrusive and costly hence actigraphy is increasingly being considered as a viable alternative. Current actigraphic sleep pattern detection algorithms ...
Introduction: Wrist-activity monitors are widely used to assess sleep and activity. Accurate measurement of time at 'lights out' (LO) is essential for calculation of several activity-derived measures including sleep latency (SL), sleep duration (SD), wake after sleep onset (WASO) and sleep efficiency (SE). To determine LO some devices use subjective ...
Purpose: We previously developed and tested the accuracy of an automated algorithm implemented using SAS to detect bed time, wake time, and sleep period time (SPT) in a sample of children. The purpose of this study was to test the accuracy of the algorithm in an adult sample. Methods: 104 adults ...
Most wearable devices that measure sedentary and active time in workplaces cannot determine the context of that time. The ActiGraph wGT3X-BT and Link models allow users to not only measure movement but the wearer's location relative to a beacon using Bluetooth proximity detection. This function has yet to be ...
Introduction. Estimating energy expenditure (EE) related to outdoor walking capacity in peripheral artery disease (PAD) patients could allow a better standardization of the assessment of their limitations during free-living outdoor walking. However, there is no data regarding the accuracy of ambulatory methods to perform such estimations. Our aim was to ...
There are no standard procedures for identifying wake wear, sleep wear and non-wear time from the 24-h accelerometer recordings. Participant diaries increase participant burden and frequently have missing values. The Choi algorithm identifies 90-min consecutive zero counts as non-wear time, allowing for 2 minutes of non-zero counts, thus possibly ignoring short ...
Introduction: Our research group has developed the processing of raw acceleration data to ActiGraph counts for improved assessment of high intensity physical activity. The aim of the present study was to apply this new processing method to large population data and investigate the effect on physical activity compared to the ...