To determine the best screening frequency the ECIBC's Guidelines Development Group (GDG) compared 3 different frequencies (annual, biennial and triennial) against each other for each age range.

Healthcare question

Should triennial vs. biennial mammography screening be used for early detection of breast cancer in women aged 45 to 49?


For asymptomatic women aged 45 to 49 with an average risk of breast cancer, the ECIBC's Guidelines Development Group (GDG) suggests either triennial or biennial mammography screening in the context of an organised screening programme. 

Recommendation strength ­

  Conditional recommendation for either the intervention or the comparison

  Very low certainty of the evidence

Considerations for implementation and policy making

  1. Examine the conditions that the GDG identified and implement according to country-priorities.
  2. If there is no breast cancer screening programme already, triennial screening may be easier to implement as compared to biennial.
  3. If screening in this age group is implemented (according to the conditional recommendation made by the ECIBC's GDG based on the screening ages) it is felt that it is better to have triennial screening than no screening programme at all.
  4. The GDG agreed that the possibility of using other imaging techniques in this subgroup of women may be relevant to consider.

Research priorities

  1. The GDG agreed that more research on the effectiveness of the different screening intervals, comparative studies, would be helpful due to the very low certainty of the evidence.

  2. Less information is available for certain outcomes in this age group (e.g. interval cancer) and this information should be shared.

  3. The GDG notes that cost-effectiveness research would be helpful to further assess this screening interval in women aged 45 to 49.

  4. There was discussion in the GDG whether women with dense breasts in this age group should be screened at different intervals.

  5. Evaluation of data on ongoing biennial opportunistic versus organised screening, particularly for this age group, and related equity issues. However, the GDG recognised that there may be difficulty and may be confounding effects when comparing different strategies for opportunistic screening.

  6. The GDG felt that increased cost effectiveness data, having more contextualised costs and cost-effectiveness analysis and from other settings would be helpful for future recommendations; this included checking the consistency of cost-effectiveness models with new research from trials on breast cancer screening and natural history of breast cancer disease. Also many countries have cost analysis but they are in the grey literature and not publicly available, and this should be shared with the scientific community.

Supporting documents