Common sense for a common problem: the question of screening the average-risk population for colorectal neoplasia.
Notice bibliographique
Résumé
here is a discrepancy between the advice given in Canada regarding screening of the average-risk population for colorectal cancer and knowledge regarding the natural history of this cancer. The benign phase of colorectal cancer development is sufficiently long and predictable to allow for its prevention. Colorectal cancer differs from breast and prostate cancer in this respect. Screening for colorectal neoplasia allows not only for the early detection of cancer during the asymptomatic stage but also for its elimination during its benign phase. The loss to the patient of a failure to screen for colorectal neoplasia is, therefore, greater than with cancers for which individuals are commonly screened. The cost of the initial care of colon cancer is several times more than for cancers of the cervix, breast or prostate. This magnifies the cost to the health care system of failure to screen for colorectal neoplasia. To justify screening an averagerisk population, the prevalence of the disease and the benefit of intervention must be sufficient. Colorectal cancer is common in Canada, affecting about 50 people per 100 000 population per year. The annual incidence increases predictably with age so that 1%, 2% and 3% of people are affected in their 50s, 60s and 70s, respectively. Without a prevention policy, 6000 in every 100 000 Canadians will develop colorectal cancer over their lifetime. The screening tool should be reliable, sensitive and capable of intervention. In the case of colorectal neoplasia, only colonoscopy fulfills these criteria. The Canadian Task Force on Preventive Health Care did not include colonoscopy in its 2001 update of guidelines regarding colon cancer, but suggested that fecal occult blood testing (FOBT) and flexible sigmoidoscopy be included in the periodic health examination of asymptomatic people over 50 years of age. 1 Even these recommendations are not as widely advocated as screening for other cancers, so their application has been limited. In effect, Canada has no policy for the prevention of colon cancer. Heightening public awareness of colon cancer requires the ready availability of a test to reassure the individual. FOBT misses most of the benign precursors of colon cancer and many of the malignant lesions. Attempts to improve the sensitivity and specificity of the test by examining feces for DNA (a panel of 21 mutations), instead of blood, have not been successful. Although the missed lesion rate dropped from 89.2% with FOBT to 81.8% with DNA, the test is, as yet, insufficiently sensitive to provide the patient or the patient’s physician with reassurance. 2 Flexible sigmoidoscopy misses between 65% and 35% of patients with advanced colonic neoplasia, and it has been suggested that the higher proportion of missed lesions occurs in women. 3
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,057 | 0,193 |
| Méta-épidémiologie (sens strict) | 0,001 | 0,001 |
| Méta-épidémiologie (sens large) | 0,003 | 0,002 |
| Bibliométrie | 0,004 | 0,003 |
| Études des sciences et des technologies | 0,011 | 0,059 |
| Communication savante | 0,011 | 0,041 |
| Science ouverte | 0,007 | 0,014 |
| Intégrité de la recherche | 0,027 | 0,047 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,007 | 0,002 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».