Variant Creutzfeldt-Jakob disease deferral in Canada: impact of stop dates.
Bibliographic record
Abstract
BACKGROUND: To reduce the risk of variant Creutzfeldt-Jakob disease (vCJD) transmission via blood transfusion in Canada, potential donors who spent a cumulative time in the United Kingdom, Western Europe or Saudi Arabia are deferred. "Stop dates" for accumulated time were later implemented for 3 months spent in the United Kingdom or France (1980-1996) and for 5 years elsewhere in Western Europe (1980-2007); Saudi Arabia deferral was implemented with the "stop date" (1980-1996). We evaluated the long-term impact of these deferrals and "stop dates", as well as the consistency of donors' answers to post-implementation screening questions. MATERIALS AND METHODS: The monthly deferral rate was monitored from 2003-2015. Time series methods (ARIMA) were used with interruption when "stop dates" were implemented. A telephone survey of 1,000 donors (250 first-time, 500 repeat deferred donors, 250 non-deferred control donors) assessed travel history (response rate 62%). An anonymous mail survey of 40,000 donors assessed compliance with deferral (response rate 45.3%). RESULTS: When the "stop date" for UK/France travel was implemented, the deferral rate decreased for first-time (2.1% to 1.1%, p<0.0001) and repeat (0.2% to 0.03%, p<0.0001) donors. The deferral rate increased after Saudi Arabia was included (mean increase of 0.4% first-time, 0.02% repeat, p<0.0001). After the Western Europe "stop date" the deferral rate was unchanged in first-time donors (1.0% to 1.1%, p=0.5) but decreased in repeat donors (0.03% to 0.02%, p<0.002). In the telephone survey, 94% of deferred donors confirmed deferrable travel history. In the anonymous survey 0.3% of donors were non-compliant with the UK/France deferral. DISCUSSION: Donors, particularly first-time ones, continue to be lost due to vCJD travel deferral, but most deferrals are correctly applied and non-compliance is rare. The application of a "stop date" reduced deferrals for UK/France travel, but it may be too early to see the full impact of the "stop date" for Western Europe.
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 | 0.002 | 0.007 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.001 |
| Bibliometrics | 0.001 | 0.002 |
| Science and technology studies | 0.002 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.000 | 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".