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 50 to 69?


For asymptomatic women aged 50 to 69 with an average risk of breast cancer, the ECIBC's Guidelines Development Group (GDG) suggests biennial mammography screening over triennial mammography screening, in the context of an organised screening programme.

Recommendation strength ­

 Conditional recommendation against the intervention

  Very low certainty of the evidence

Considerations for implementation and policy making

The GDG felt that selection of the screening interval should be dependent on the resources available in a specific country, including the sustainability of the costs and resources available.

In contexts where screening programmes do not already exist, the GDG felt that it would be better to have a 3-year screening interval than no screening programme at all.

In contexts where a 3-year screening interval is currently used, the GDG recognised that human resource (radiologists/radiographers) availability may determine the decision.

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. The GDG felt that the implications of breast density on appropriate screening intervals should be prioritised as this could be a risk modifier that may need different intervals.
  3. The GDG discussed the need for improved knowledge on radiation dose and the differences that screening intervals would have on the radiation dose received by women.
  4. 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