The Canadian CT Head Rule reduced the need for CT scans more than the New Orleans Criteria in minor head injury
Bibliographic record
Abstract
Smits M, Dippel DW, de Haan GG, et al. External validation of the Canadian CT Head Rule and the New Orleans Criteria for CT scanning in patients with minor head injury. JAMA 2005;294:1519–25. [OpenUrl][1][CrossRef][2][PubMed][3][Web of Science][4] Q In patients with minor head injury, how do the Canadian CT Head Rule (CCHR) and the New Orleans Criteria (NOC) compare for selecting which patients should receive computed tomography (CT) scanning? Clinical impact ratings Emergency medicine ★★★★★★☆ Surgery—neurosurgery ★★★★★★☆ ### ![Graphic][5] Design: external validation of 2 previously developed clinical prediction guides (CCHR and NOC). ### ![Graphic][6] Setting: 4 university hospitals in the Netherlands. ### ![Graphic][7] Patients: 3181 patients ⩾16 years of age (mean age 41 y, 71% men) who presented within 24 hours after blunt head injury and had a Glasgow Coma Scale (GCS) score of 13–14 or 15 with 1 of the following: history of loss of consciousness, short term memory deficit, amnesia for the traumatic event, post-traumatic seizure, vomiting, severe headache, intoxication with alcohol or drugs, use of anticoagulants or history of coagulopathy, injury above the clavicles, or neurological deficit. Patients who could not receive a CT scan because of concurrent injury … [1]: {openurl}?query=rft.jtitle%253DJAMA%26rft.stitle%253DJAMA%26rft.issn%253D0002-9955%26rft.aulast%253DSmits%26rft.auinit1%253DM.%26rft.volume%253D294%26rft.issue%253D12%26rft.spage%253D1519%26rft.epage%253D1525%26rft.atitle%253DExternal%2BValidation%2Bof%2Bthe%2BCanadian%2BCT%2BHead%2BRule%2Band%2Bthe%2BNew%2BOrleans%2BCriteria%2Bfor%2BCT%2BScanning%2Bin%2BPatients%2BWith%2BMinor%2BHead%2BInjury%26rft_id%253Dinfo%253Adoi%252F10.1001%252Fjama.294.12.1519%26rft_id%253Dinfo%253Apmid%252F16189365%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [2]: /lookup/external-ref?access_num=10.1001/jama.294.12.1519&link_type=DOI [3]: /lookup/external-ref?access_num=16189365&link_type=MED&atom=%2Febmed%2F11%2F2%2F61.atom [4]: /lookup/external-ref?access_num=000232113400022&link_type=ISI [5]: /embed/inline-graphic-1.gif [6]: /embed/inline-graphic-2.gif [7]: /embed/inline-graphic-3.gif
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
Direct model labels (unvalidated)
Per-model category and study-design labels from the labeling rounds. They are machine output, unvalidated, and the disagreement between models ships as data. No study design here is MEDLINE-validated yet.
| Model arm | Categories | Study design | Confidence |
|---|---|---|---|
| gemma | no category Domain: not available · Genre: Empirical About the Canadian research system: no · About a Canadian topic: no | Observational | low |
| gpt | no category Domain: not available · Genre: Commentary About the Canadian research system: no · About a Canadian topic: no | Not applicable | high |
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 | 0.010 | 0.067 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.001 | 0.002 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.007 | 0.001 |
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, unvalidatedLabeled directly by 2 models reading the full record.
The models disagree on parts of this classification; every voice is preserved in the section at the end of the page.
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".