Temporal trends in the sit-ups performance of 9,939,289 children and adolescents between 1964 and 2017
Bibliographic record
Abstract
We estimated international/national temporal trends in sit-ups performance for children and adolescents, and examined relationships between national trends in sit-ups performance and national trends in health-related/sociodemographic indicators. Data were obtained by systematically searching studies reporting on temporal trends in sit-ups performance for apparently healthy 9-17 year-olds, and by examining nationally representative fitness datasets. Trends at the country-sex-age level were estimated by sample-weighted regression models relating the testing year to mean sit-ups performance. International/national trends were estimated by a post-stratified population-weighting procedure. Pearson's correlations quantified relationships between national trends in sit-ups performance and national trends in health-related/sociodemographic indicators. A total of 9,939,289 children and adolescents from 31 countries/special administrative regions between 1964 and 2017 collectively showed a large improvement of 38.4% (95% CI: 36.8 to 40.0) or 7.1% per decade (95% CI: 6.8 to 7.4). Large international improvements were experienced by all age and sex groups, with the rate of improvement slowing from 1964 to 2000, stabilizing near zero until 2010, before declining. Trends differed between countries, with national trends in vigorous physical activity a strong, positive correlate of national trends in sit-ups performance. More sit-ups data are needed from low- and middle-income countries to better monitor trends in muscular fitness. PROSPERO REGISTRATION NUMBER: CRD42013003657.
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How this classification was reachedexpand
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 | 0.001 | 0.000 |
| 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 itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, 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".