A latent transition analysis of a cluster randomized controlled trial for drug use prevention.
Bibliographic record
Abstract
OBJECTIVE: The objective of the study was to evaluate the impact of #Tamojunto, a Brazilian adaptation of the Unplugged prevention program, on patterns of drug use among adolescents and to characterize their trajectories of drug use over time. METHOD: An in-cluster randomized controlled trial was conducted in 2014-2015 with 2 parallel arms (intervention and control). The intervention group attended 12 weekly classes of the #Tamojunto intervention. The control schools did not offer a prevention program. The target population was students attending seventh and eighth grades. The primary dichotomous outcome measures were use of drugs (any alcohol use, binge drinking, tobacco, marijuana, inhalants, and cocaine) in the past year assessed using a questionnaire before intervention and in 2 waves of follow-up (9 and 21 months). RESULTS: A latent transition analysis in 6,391 students from 72 public schools in 6 Brazilian cities revealed 3 distinct patterns of drug use behavior: abstainers/low users (81.54% at baseline, 70.61% after 21 months), alcohol users/binge drinkers (16.65% at baseline, 21.45% after 21 months), and polydrug users (1.80% at baseline, 7.92% after 21 months). No differences in the probabilities of transitions between these drug use patterns were found between the intervention and control groups. The most likely trajectory was no transition between patterns, regardless of the intervention and baseline pattern. CONCLUSIONS: The intervention was not successful in changing adolescent drug use patterns over time, showing that the components of the Brazilian adaptation of the Unplugged prevention program should be reevaluated. (PsycINFO Database Record
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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 | 0.027 | 0.038 |
| Meta-epidemiology (narrow) | 0.002 | 0.001 |
| Meta-epidemiology (broad) | 0.007 | 0.009 |
| Bibliometrics | 0.002 | 0.001 |
| Science and technology studies | 0.001 | 0.002 |
| Scholarly communication | 0.002 | 0.002 |
| Open science | 0.001 | 0.002 |
| Research integrity | 0.002 | 0.004 |
| Insufficient payload (model declined to judge) | 0.014 | 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".