DOES FREQUENCY (HZ) AND ACCELERATION OF MOVEMENT AFFECT THE RELIABILITY OF THE MTI(CSA) ACTIGRAPH?
Bibliographic record
Abstract
The link between physical activity and health has caused a surge in physical activity research. It is essential that movement assessment devices be both valid and reliable. PURPOSE To determine the effect of acceleration and frequency (Hz) on the intra- and inter-instrument reliability of the MTI Actigraph. METHODS The MTI Actigraph is a uniaxial accelerometer designed to measure accelerations from approximately 0.5–19.5 m/s2 at frequencies ranging from 0.25–2.5 Hz. Seventy-five Actigraphs were placed on a hydraulic shaker plate and accelerated in the vertical plane at varying accelerations and frequencies. Five different, five minute conditions were used to produce a range of physiologically relevant counts. Reliability was calculated using standard error of the measurement (SEM), coefficient of variation (CV), and correlation coefficients (Corr.) RESULTS See Table.Table: No Caption AvailableCONCLUSIONS The inter- and intra-instrument counts generated by the MTI Actigraph were found to be reliable (r > 0.80) across the range of frequencies (Hz) and accelerations tested. However, these results do not address the validity of the device as a physical activity monitor. Supported by the NSERC.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.014 | 0.092 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.001 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.001 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".