Reliability and validity of the Performance Recorder 1 for measuring isometric knee flexor and extensor strength
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
BACKGROUND: Muscular strength is a key parameter of rehabilitation programs and a strong predictor of functional capacity. Traditional methods to measure strength, such as manual muscle testing (MMT) and hand-held dynamometry (HHD), are limited by the strength and experience of the tester. The Performance Recorder 1 (PR1) is a strength assessment tool attached to resistance training equipment and may be a time- and cost-effective tool to measure strength in clinical practice that overcomes some limitations of MMT and HHD. However, reliability and validity of the PR1 have not been reported. METHODS: Test-retest and inter-rater reliability was assessed using the PR1 in healthy adults (n = 15) during isometric knee flexion and extension. Criterion-related validity was assessed through comparison of values obtained from the PR1 and Biodex® isokinetic dynamometer. RESULTS: Test-retest reliability was excellent for peak knee flexion (intra-class correlation coefficient [ICC] of 0.96, 95% CI: 0.85, 0.99) and knee extension (ICC = 0.96, 95% CI: 0.87, 0.99). Inter-rater reliability was also excellent for peak knee flexion (ICC = 0.95, 95% CI: 0.85, 0.99) and peak knee extension (ICC = 0.97, 95% CI: 0.91, 0.99). Validity was moderate for peak knee flexion (ICC = 0.75, 95% CI: 0.38, 0.92) but poor for peak knee extension (ICC = 0.37, 95% CI: 0, 0.73). CONCLUSIONS: The PR1 provides a reliable measure of isometric knee flexor and extensor strength in healthy adults that could be used in the clinical setting, but absolute values may not be comparable to strength assessment by gold-standard measures.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.002 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
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 it