Preventive health care, 2001 update: screening mammography among women aged 40-49 years at average risk of breast cancer.
Bibliographic record
Abstract
OBJECTIVE: A previous review by the Canadian Task Force on the Periodic Health Examination (now the Canadian Task Force on Preventive Health Care) in 1994 indicated fair evidence to exclude mammographic breast cancer screening of women aged 40-49 from the periodic health examination. This current review considers the available new and updated evidence regarding the effect of screening mammography on breast cancer mortality among women in this age group at average risk of breast cancer. OPTIONS: Screening mammography starting at either age 40 or age 50. OUTCOME: Reduction in breast cancer mortality. EVIDENCE: The MEDLINE and CANCERLIT databases were searched for relevant articles published from 1966 to January 2000. Of 68 references obtained, at least 22 were published after the 1994 review. To date, the only trial designed to assess the mortality benefits of screening mammography among women aged 40-49 did not have adequate power to exclude a clinically significant benefit. Other results from randomized controlled trials (RCTs) are post-hoc subgroup analyses of larger trials. BENEFITS, HARMS AND COSTS: Screening mammography offers the potential for significant benefits in addition to mortality reduction, including early diagnosis, less aggressive therapy and improved cosmetic results. However, the risks of screening include increased biopsy rates and the psychological effects of false reassurance or false-positive results. Although several of the trials reviewed constitute level I evidence (RCT), at present their conflicting results, methodologic differences and, most important, uncertainty about the risk:benefit ratio of screening precludes the assignment of a "good" or "fair" rating to recommendations drawn from them. VALUES: The strength of evidence was evaluated using the methods of the Canadian Task Force on Preventive Health Care. A high value was placed on changes in survival. When evidence was available, value was also placed on potential quality-of-life implications. RECOMMENDATION: Current evidence regarding the effectiveness of screening mammography does not suggest the inclusion of the manoeuvre in, or its exclusion from, the periodic health examination of women aged 40-49 years at average risk of breast cancer (grade C recommendation). Upon reaching the age of 40, Canadian women should be informed of the potential benefits and risks of screening mammography and assisted in deciding at what age they wish to initiate the manoeuvre. VALIDATION: The findings of this analysis were reviewed through an iterative process by the members of the Canadian Task Force on Preventive Health Care. SPONSORS: The Canadian Task Force on Preventive Health Care is funded through a partnership between the Provincial and Territorial Ministries of Health and Health Canada.
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 | 0.005 | 0.022 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.003 | 0.002 |
| Bibliometrics | 0.008 | 0.007 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.002 | 0.002 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.002 | 0.002 |
| Insufficient payload (model declined to judge) | 0.008 | 0.002 |
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".