A Comparison of 2 Methods of Continuous Aerosol Administration During Methacholine Challenge Testing
Bibliographic record
Abstract
BACKGROUND: Exposure to the bronchoconstricting agent methacholine is a potential hazard to technical staff during methacholine challenge testing, which remains a useful and frequently performed test. There are several methods of performing the test. One of the 2 methods listed in the American Thoracic Society's guidelines is the 2-min tidal-breathing method. The methacholine can be inhaled using one of several methods. The loosely-fitting-mask method is likely to produce more contamination of the local environment than a filtered exhalation system. METHODS: We tested 2 variations of the tidal-breathing method of measuring the methacholine provocational concentration (PC(20), the dose that produces a 20% decrease in forced expiratory volume in the first second). One involved use of the open-mask technique and the other a T-piece-and-filter system that precluded the release of methacholine-containing droplets into the environment. We performed duplicate methacholine challenge tests with 10 subjects who had a wide range of PC(20). The tests were done in random order, and each subject performed one test using the mask and one using the T-piece/filter system. RESULTS: With the mask system the geometric mean PC(20) was 4.7 mg/mL, versus 5.1 mg/mL with the T-piece-filter system (p = 0.36). These values are very close and would not be substantially different clinically. CONCLUSION: The 2 methods are equivalent, and the low cost of the products used in the T-piece/filter method makes it suitable for reducing technician exposure to methacholine, using potentially completely disposable components.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot 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.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 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 teacher head, 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".