Prevalence and correlates of meeting physical activity, screen time, and sleep duration guidelines among Brazilian adolescents: findings from ERICA
Bibliographic record
Abstract
The prevalence of meeting movement guidelines is low in developed countries; however, there is a lack of data among medium-income countries, including Brazil. We evaluated the prevalence and correlates of meeting physical activity, screen time, and sleep guidelines in Brazilian adolescents. Employing a cross-sectional design, Brazilian adolescents (aged 12–17 years) were surveyed about their physical activity levels, sleep, and screen time. Data were collected at schools through a self-administered questionnaire using a personal digital assistant for entering the data. Poisson regression models were used to examine the associations between correlates (sex, age, socioeconomic status, region, skin colour, and shift of school) and meeting movement guidelines. A total of 58 535 adolescents were included. Although only 8.7% of the adolescents met all three movement guidelines, the prevalence of those who met physical activity, screen time, and sleep duration guidelines was 46.4%, 42.5%, and 40%, respectively. Moreover, male sex, age 14–15 years, black or brown skin colour, afternoon shift of school, and living in the Northern and Northeastern regions were associated with a higher prevalence of meeting all movement guidelines. The prevalence of adolescents who met all three movement guidelines was low among Brazilian adolescents. Adolescents living in less developed regions showed greater adherence to movement guidelines, suggesting a possible impact of the urbanization process on these behaviours. Novelty: The prevalence of Brazilian adolescents who met all three movement behaviour guidelines was around 9%. Among all adolescents, 40% met only one movement guideline.
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.
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 | 0.001 | 0.004 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.001 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 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 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".