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Record W2030515350 · doi:10.1111/birt.12014

Quantifying <scp>VBAC</scp> Risk: Muddying the Waters

2012· letter· en· W2030515350 on OpenAlexaffabout
Andrew Kotaska

Bibliographic record

VenueBirth · 2012
Typeletter
Languageen
FieldMedicine
TopicMaternal and Perinatal Health Interventions
Canadian institutionsUniversity of ManitobaIndustry, Tourism and InvestmentGovernment of Northwest TerritoriesUniversity of British Columbia
Fundersnot available
KeywordsMedicineObstetricsUterine rupturePregnancyVaginal deliveryGestationVaginal birthProspective cohort studyQuarter (Canadian coin)Elective cesarean sectionPediatricsSurgeryUterus

Abstract

fetched live from OpenAlex

The Landon et al and the Crowther et al papers are both prospective trials comparing planned vaginal birth after a previous cesarean section (VBAC) with elective cesarean section in women eligible for a trial of labor. With 33,000 women, the cohort studied by Landon et al in conjunction with the National Institute of Child Health and Human Development (NICHHD) spawned multiple publications, giving estimates of VBAC risks and success relevant to women in a wide variety of clinical situations. Data abstraction was careful and outcomes were hard and verified. With 2,300 women, the study by Crowther et al, was 6 percent the size of the Landon-NICHHD study. Although it claimed "increased risk of both fetal death or liveborn infant death prior to discharge or serious infant outcome," there were only 2 perinatal deaths-both stillbirths prior to 39 weeks' gestation and unrelated to mode of delivery. Of the 28 infants with "serious neonatal morbidity," only three could have resulted from uterine rupture; prior experience with this outcome indicates all three will likely escape long-term morbidity. Pseudorandomization and erroneous adherence to an intention-to-treat principle seriously hinder the study's internal validity, attributing outcomes for one quarter of women undergoing elective cesarean section to the planned VBAC group. The study by Landon and NICHHD is over 10 times larger and of much higher quality than the study by Crowther et al. The Landon-NICHHD publications should be used to help women make decisions about planned mode of delivery after cesarean.

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 distilled prediction

Teacher imitation

Not 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.

metaresearch head score (Codex)0.000
metaresearch head score (Gemma)0.000
Version: codex-gemma-dda1882f352aValidation status: machine_predicted_unvalidated
Candidate categoriesInsufficient payload (model declined to judge)
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Not applicable · Consensus signal: Not applicable
GenreCandidate signal: Commentary · Consensus signal: Commentary
Teacher disagreement score0.237
Threshold uncertainty score0.999

Codex and Gemma teacher scores by category

CategoryCodexGemma
Metaresearch0.0000.000
Meta-epidemiology (narrow)0.0000.000
Meta-epidemiology (broad)0.0000.000
Bibliometrics0.0000.000
Science and technology studies0.0000.000
Scholarly communication0.0000.000
Open science0.0000.000
Research integrity0.0000.002
Insufficient payload (model declined to judge)0.0010.002

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.

Opus teacher head0.085
GPT teacher head0.336
Teacher spread0.251 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it

Classification

machine, unvalidated

Machine predicted; a candidate call from one teacher head, not a consensus.

Study designNot applicable
Domainnot available
GenreCommentary

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".

Quick stats

Citations4
Published2012
Admission routes2
Has abstractyes

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