Prospective Evaluation of the Prevalence of Pulmonary Embolism in Patients with Chronic Obstructive Pulmonary Disease Exacerbation: Challenges and Feasibility
Bibliographic record
Abstract
Introduction: Data on the prevalence of pulmonary embolism (PE) in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) in North America is lacking, with most of the prospective studies conducted in Europe and Asia. The aim of this study is to describe feasibility of prospective collection of data evaluating the prevalence of PE in patients admitted for AECOPD in Canada, and to describe challenges of this approach. Methods: This is a secondary analysis of a prospective pilot patient cohort aiming to assess the diagnosis of AECOPD among hospitalized patients. Items of the Wells PE and revised Geneva scores were prospectively collected. All patients underwent D-dimer testing within 24 hours of admission. All patients were followed for 3 months. Feasibility outcomes were prospective data collection to evaluate the prevalence of PE, D-dimer level measurement and 3-month follow-up. The study was considered feasible if >=90% of the patients had prospective data collected to assess the prevalence of PE, >=80% of the patients had D-dimer level measured and their 3-month follow-up, respectively. Challenges were also assessed. Results: Twenty patients were included. According to the Wells PE score, 16 (80.0%), 4 (20.0%) and 0 (0.0%) patients had low, moderate and high clinical pre-test probability (c-PTP), respectively. According to the revised Geneva score, 2 (10.0%), 17 (85.0%) and 1 (5.0%) patients had low, intermediate and high c-PTP, respectively. Based on age-adjusted D-dimer cut-off, 7 and 11 patients had negative and positive D-dimer, respectively. All patients (100.0%) had prospective data collection to assess the prevalence of PE. D-dimer level was available for 18/20 (90.0%) patients and 3-month follow-up evaluation was performed in 16/20 (80.0%) patients. Challenges included the difficulty in recruiting patients since it is a population with many comorbidities, adequate c-PTP assessment using validated clinical decision rules, absence of consistent PE diagnostic strategy use since patients were mostly investigated according to the physician's impression and adequate 3-month follow-up since 25% of the patients had some protocol deviation for the follow-up. No PE was diagnosed during the entire study period. Conclusion: This pilot study shows the feasibility in prospectively collecting data to evaluate the prevalence of PE in patients admitted for AECOPD in Canada. Also, challenges were assessed and included recruitment of patients, adequate c-PTP assessment, consistent PE diagnostic strategy use and adequate 3-month follow-up.
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 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 | 0.023 | 0.029 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.002 | 0.002 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.002 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 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".