Axivity
Axivity AX6 Accelerometer wristband
About#
The Axivity AX6 is a research-grade accelerometer consisting of a small sensor unit (the "puck") housed in a rubber wristband. Before each recording period, it will be configured at the site using the open-source OmGui software to record raw tri-axial acceleration continuously at 100 Hz with a ±16 g dynamic range, written directly to onboard memory. The device will be fully charged before deployment, and will not need to be charged during the recording period. It will be worn overnight on the child's non-dominant wrist. Because the AX6 stores data locally rather than uploading, its recordings cannot be checked remotely during the period; on return to the site, recording is stopped in OmGui, the .cwa file is extracted from the puck, and the data are uploaded to Lasso.
Raw tri-axial acceleration data undergo standardized processing. Periods of non-wear are first identified and removed; the remaining signal is then segmented into epochs and classified as sleep or wake using a validated algorithm to derive the relevant sleep variables, including total sleep time (TST), wake after sleep onset (WASO), sleep efficiency, and number of awakenings.
Administration
| Administration type | Direct Assessment |
|---|---|
| Setting | Remote |
| Duration | 6-12 hr sleep x 3 days |
| Respondent | Child |
| Visits | Visits 1-3 |
| Ages |
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