Health services for gastroesophageal reflux disease: An evaluation of the use of antireflux surgery in Ontario
Bibliographic record
Abstract
The main objective of this thesis was to evaluate the utilization of antireflux surgery in Ontario from a health services perspective. First, we examined the rates of utilization and variation of antireflux surgery across the province of Ontario. Second, we assessed the accuracy of GERD-related diagnosis coding in Ontario's administrative health databases. Finally, a retrospective inception cohort of patients was created to study the determinants of antireflux surgery. Significant regional variation exists for antireflux surgery across Ontario, suggesting that antireflux surgery is a highly "discretionary" procedure. Gastrointestinal diagnostic codes are highly specific but sensitivity is poor. The most important determinant of surgery in GERD appears to be specialist enthusiasm for surgery. Rates of antireflux surgery varied by as much as 6-fold across the province of Ontario. The sensitivity and specificity for esophagitis were 46.8%, and 98.8% respectively. The variable most strongly associated with surgery was physician specialty.
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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 | 0.001 | 0.003 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.004 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 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".