Prevalence and Trends of Sexual Behaviors Among Young Adolescents Aged 12 Years to 15 Years in Low and Middle-Income Countries: Population-Based Study
Bibliographic record
Abstract
BACKGROUND: Risky sexual behaviors remain significant public health challenges among adolescents. Nearly 90% of adolescents live in low and middle-income countries (LMICs), but few studies have used standardized methodology to monitor the prevalence and trends of sexual behaviors among adolescents in LMICs. OBJECTIVE: This study aimed to assess the prevalence of sexual behaviors (ever had sexual intercourse, multiple sexual partners, and condom use) among adolescents aged 12 years to 15 years as well as the trends in prevalence between 2003 and 2017. METHODS: For this population-based study, we used recent data from the Global School-based Student Health Survey conducted in 69 LMICs from 2003 to 2017 to assess the recent prevalence of sexual behaviors by using complex analysis and a random effects meta-analyses method. Using the chi-square trend test, we also assessed the trends in the prevalence of sexual behaviors in 17 countries that had conducted ≥1 round of surveys from 2003 to 2017. RESULTS: We included 145,277 adolescents aged 12 years to 15 years (64,719/145,277, 44.5% boys) from the 69 LMICs that had conducted ≥1 survey and 80,646 adolescents aged 12 years to 15 years (34,725/80,646, 43.1% boys) from the 17 LMICs that had conducted ≥1 round of surveys. The recent global prevalence of ever had sexual intercourse was 6.9% (95% CI 6.2%-7.6%) and was higher among boys (10.0%, 95% CI 9.1%-11.1%) than girls (4.2%, 95% CI 3.7%-4.7%) and among those aged 14 years to 15 years (8.5%, 95% CI 7.7%-9.3%) than those aged 12 years to 13 years (4%, 95% CI 3.4%-4.7%). Among adolescents who had ever had sex, the recent global prevalence of having multiple sexual partners was 52% (95% CI 50.4%-53.6%) and was higher among boys (58%, 95% CI 56.1%-59.9%) than girls (41.4%, 95% CI 38.9%-43.9%) and among those aged 14 years to 15 years (53.5%, 95% CI 51.6%-55.4%) than those aged 12 years to 13 years (49.7%, 95% CI 45.9%-53.5%). Among adolescents who had ever had sex, the recent global prevalence of condom use was 58.1% (95% CI 56.2%-59.9%) and was higher among girls (59.2%, 95% CI 56.4%-61.9%) than boys (57.7%, 95% CI 55.7%-59.7%) and among those aged 14 years to 15 years (59.9%, 95% CI 58.0%-61.8%) than those aged 12 years to 13 years (51.6%, 95% CI 47.5%-55.7%). Between the earliest and latest surveys, the overall prevalence of ever had sexual intercourse (3.1% decrease) and condom use (2.0% decrease) showed downward trends. The overall prevalence of having multiple sexual partners increased by 2.6%. CONCLUSIONS: We provide evidence and important implication for policymakers to develop targeted policy support systems to prevent and reduce risky sexual behaviors among young adolescents in LMICs with a high prevalence of risky sexual behaviors.
Stored with the screening record, where it is evidence for the labels above.
How this classification was reachedexpand
The three-model screen
all 5,600 screened works →All three models called this out of scope.
Population-based study of adolescent sexual behaviour prevalence and trends in low- and middle-income countries; an epidemiological question.
The meta-analysis uses a synthesis method to study adolescent sexual behaviors rather than synthesis methodology.
Public-health epidemiology of adolescent sexual behaviours in LMICs; uses surveys, does not study methods.
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 | 0.002 | 0.003 |
| Meta-epidemiology (narrow) | 0.000 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.002 | 0.003 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| 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".