Trend in prevalence of neural tube defects in Quebec
Bibliographic record
Abstract
BACKGROUND: In Canada, the first recommendations on the use of folic acid (FA) supplements by women planning a pregnancy or capable of becoming pregnant were issued in 1993. In 1998, fortification of flour with FA became mandatory. The objective of this study was to assess the impact of these measures on the prevalence of neural tube defects (NTDs) in the province of Quebec. METHODS: The study population included stillbirths, live births, and elective terminations for fetal malformations that were reported in 1992-2000 for women residing in the province of Quebec. NTD cases were identified from stillbirth certificates and hospital discharge summaries. RESULTS: There was a marked decrease in the total NTD rate after 1997. The average NTD rate was 1.89 per 1000 total births during the period of 1992-1997, and 1.28 per 1000 in 1998-2000, a 32% reduction (p < 0.001). CONCLUSIONS: Fortification of flour, which began in early 1997 and gradually became widespread, is a very plausible explanation for the timing, shape, and magnitude of the decrease in NTD prevalence observed in Quebec and other Canadian provinces. An increase in FA supplement use may have played only a minor role. Birth Defects Research (Part A) 67:000-000, 2003.
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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 | 0.000 | 0.002 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.002 | 0.002 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.004 | 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".