Guidance

Breast screening supporting information

Updated 4 May 2023

Applies to England

Introduction

These revised screening standards for the NHS Breast Screening Programme (BSP) replace previous versions. They apply for data collected from 1 April 2021 unless stated otherwise in the document.

The UK National Screening Committee (UK NSC) recommends all eligible women aged 50 up to their 71st birthday are invited to breast screening every 3 years. Screening aims to detect breast cancers at the earliest opportunity, maximise the success of treatment and reduce mortality from breast cancer.

There are a number of categories of women in the eligible age range who are not registered with a GP and subsequently not called for screening as they are not on the Breast Screening Select (BS Select) database. Screening services have a responsibility to maximise coverage of eligible women in their target population and should therefore be accessible to women in this category through self-referral.

Additionally, women identified as being at very high risk of breast cancer should be referred into the NHS BSP for annual invitation. The categories of women which are eligible for very high risk screening are outlined in the very high risk women surveillance protocols. The NHS BSP has responsibility for implementing this policy.

The programme service specification (No. 24) for the NHS providers is available as part of the public health functions exercised by NHS England.

We aim to make sure there is equal access to uniform and quality assured screening across England and that women are provided with high quality information so they can make an informed choice about whether to attend breast screening.

Screening guidance documents on GOV.UK may link to a central glossary of terms, ‘NHS population screening explained’ and NHS UK for definition of terms. To see the meaning of an acronym, hover over it with your cursor to see the full definition.

Several standards are split into 2 parts: the prevalent screen and the incident screen.

Prevalent screen

The prevalent screen is the first screen. It should take place between the age of 50 to less than 53 years (52 years and 364 days). Women in the age extension cohort trial (AgeX) should be monitored from the age of 45 to 52 as they could not be excluded from the routine prevalent screening cohort. For this reason, prevalent screen age range is monitored from 45 to less than 53 years.

Due to the way the KC62 return is reported, women with a prevalent screen between the age of 47 and 49 are reported in a 5 year age band of 45 to 49. This is why the age range in the standards definitions are described as 45 to less than 53.

Some women may not attend their first invitation and may have their prevalent screen after the age of 53. For standards BSP-S14 and BSP-S16 the prevalent screen is measured from age 45 to less than 71 (60 years and 364 days) in order to include cancers from the full eligible age group.

Incident screen

The incident screen refers to subsequent screens and is measured from 50 to less than 71. This is so that women from the AgeX trial who had their prevalent screen before the age of 50 have any incident screens between 50 and 53 included.

The trial is not part of routine screening and we include some trial women in screening standards because we cannot exclude them and continue to monitor programme performance adequately. For the reasons outlined above, the incident screen age range is monitored from 50 to less than 71.

For the age extension cohort aged 71 to 73, they are not included in the calculation of programme standards, as their statistics are separated from the routine screening cohort (age 50 to less than 71). Hence, we include trial women in the prevalent screen cohort but not when monitoring the incident (subsequent) screen.

Standards BSP-S03 (uptake), BSP-S04 (screening round length), BSP-S06 (timeliness of screening results letters that do not require further assessment) and BSP-S07 (rate of referral to assessment) are split into routine screening and very high risk screening.

Summary of changes from previous version of standards

Previous BSP measurable standards were documented in the programme guidance.

Programme guidance continues to be provided and will cover the screening standards as featured in the section 7a service specification.

Throughout this document and the standards definitions when the term ‘cancer’ is used it refers to breast cancer.

BSP-S01: uptake: timely invitation for screening – shadow

New standard introduced in shadow form for the first 12 months before thresholds can be considered.

BSP-S01: coverage

Now standard BSP-S02. The caveats section has been updated to include women registered with a GP but have no address on Spine.

BSP-S02: uptake

Now standard BSP-S03. The standard has been split into 2 parts – routine screening and very high risk screening. The thresholds for very high risk screening are based on data from 2018 to 2019.

BSP-S03: uptake: screening round length

Now standard BSP-S04. The standard has been split into 2 parts – routine screening and very high risk screening. The very high risk screening part will be in shadow format for a year while reports to support the standard are developed and data is collected. The achievable threshold for routine screening has been lowered to greater than or equal to 99.0% following national screening guidance. The caveats have been updated.

BSP-S04: test: repeat examination rate

Now standard BSP-S05. The standard has been renamed repeat mammography rate so that consistent terminology is used through the standard. The standard has been split into 2 parts – technical recall and technical repeat. The thresholds have been set based on the interquartile range of 2018 to 2019 data.

BSP-S05: test: recording appropriate radiation dose

This has been removed as a screening standard but will remain as a standard in the commissioning and testing of full field digital mammography systems guidance. As quality and maintenance of equipment is an important aspect of delivering screening it will also still be monitored through quality assurance visits. The standard was removed because it was not measurable at a service level. It is a structural standard and should be carried out for every piece of equipment.

BSP-S06: test: image quality

This has been removed as a screening standard but will remain as a standard in the commissioning and testing of full field digital mammography systems guidance. As quality and maintenance of equipment is an important aspect of delivering screening it will also still be monitored through quality assurance visits. The standard was removed because it was not measurable at a service level. It is a structural standard and should be carried out for every piece of equipment.

BSP-S07: test: receipt of screening results

Now standard BSP-S06. This standard has been renamed timeliness of screening results letters that do not require further assessment as this is a more accurate reflection of what the standard is measuring. The standard has been split into 2 parts – routine screening and very high risk screening. Clarification to how the standard is calculated for women who have a technical recall has been added. The achievable threshold has been lowered to greater than or equal to 99.0% following national screening guidance.

BSP-S08: referral: referral to assessment rate

Now standard BSP-S07. The rate of referral to assessment for women on very high risk screening has been added.

The acceptable threshold for BSP-S07a has reduced from less than 10.0% to less than 9.0% based on the lower quartile of data for 1 April 2016 to 31 March 2019. For BSP-S07b the acceptable threshold has reduced from less than 7.0% to less than 4.0%. The achievable threshold has reduced from less than 5.0% to less than 3.0%. The thresholds were set based on the interquartile range of data for 1 April 2016 to 31 March 2019.

BSP-S09: diagnosis and or intervention: short-term recall rates

Now standard BSP-S08. There have been minor changes to the wording of the rational and definition.

BSP-S10: referral: time to first offered appointment for assessment

Now standard BSP-S09. The standard has been split into 2 parts - routine screening and very high risk screening. The acceptable threshold for routine screening has been lowered from greater than 98.0% to greater than or equal to 95.0%. The achievable level has lowered from 100% to greater than or equal to 99.0%.

BSP-S11: diagnosis and or intervention: number of assessment visits to obtain a definitive diagnosis

Now standard BSP-S10. Minor wording changes to the description.

BSP-S12: diagnosis and or intervention: benign biopsies rates

Now standard BSP-11. The standard has been renamed rates of benign open biopsies.

BSP-S13: diagnosis and or intervention: rates of non-operative diagnosis

Now standard BSP-12. The definition is separated into invasive and non-invasive disease in line with the different performance thresholds. The acceptable threshold for invasive malignancy has increased from greater than or equal to 90.0% to greater than or equal to 99.0% and there is no achievable threshold. For non-invasive carcinoma, the acceptable threshold has increased from greater than or equal to 85.0% to greater than or equal to 90.0% and the achievable threshold from greater than or equal to 90.0% to greater than or equal to 95.0%. The thresholds were set based on the interquartile range of data for 1 April 2016 to 31 March 2019.

BSP-S13: referral: positive predictive value of referral

New standard. Thresholds set based on the interquartile range of data for 1 April 2016 to 31 March 2019.

BSP-S14: diagnosis and or intervention: age standardised detection ratios (SDRs) for invasive cancers

A 20% increase on the original expected levels has been used to account for the increase in background incidence of invasive breast cancer in the population since the previous rates were applied in 1993. Due to the increase in the expected levels the thresholds have been adjusted accordingly. The caveats have been updated accordingly.

BSP-S15: diagnosis and or intervention: small cancer age standardised detection ratios (SDRs) for invasive cancers

A 20% increase on the original expected levels has been used to account for the increase in background incidence of invasive breast cancer in the population since the previous rates were applied in 1993. Due to the increase in the expected levels the thresholds have been adjusted accordingly. The caveats have been updated accordingly.

BSP-S16: diagnosis and or intervention: non-invasive cancer detection rates

Caveats have been updated.

BSP-S17: diagnosis and or intervention: staging of the axilla

This standard has been removed but will continue to be monitored in the NHS BSP and Association of Breast Surgery (ABS) annual audit. The standard was removed because there are issues with the sensitivity of the test. It also falls outside the scope of the screening pathway.

BSP-S18: outcome: rates of interval cancers

Now standard BSP-S17. The definition has been split into 3 parts to match the 3 different acceptable thresholds.

Pathway themes

NHS BSP screening standards look at 6 themes (listed below) to assess the pathway, and 2 key performance indicators (KPIs) are derived from standards BSP-S03a and BSP-S04a.

Theme: coverage

The related standard is BSP-S02: coverage

Theme: uptake

Related standards are:

BSP-S01: uptake: timely invitation for screening

BSP-S03: uptake

BSP-S04: uptake: screening round length

Theme: test

Related standards are:

BSP-S05: test: repeat examination rate

BSP-S06: test: timeliness of screening results letters that do not require further assessment

Theme: referral

Related standards are:

BSP-S07: referral: rate of referral to assessment

BSP-S09: referral: time to first offered appointment for assessment

BSP-S13: referral: positive predictive value of referral

Theme: diagnosis and intervention

Related standards are:

BSP-S08: diagnosis and or intervention: short-term recall rates

BSP-S10: diagnosis and or intervention: definitive diagnosis of cancer made in less than or equal to 3 assessment visits

BSP-S11: diagnosis and or intervention: rates of benign open biopsies

BSP-S12: diagnosis and or intervention: rates of non-operative diagnosis

BSP-S14: diagnosis and or intervention: age standardised detection ratios (SDRs) for invasive cancers

BSP-S15: diagnosis and or intervention: small cancer age standardised detection ratios for invasive cancers

BSP-S16: diagnosis and or intervention: non-invasive cancer detection rates

Theme: outcome

The related standard is BSP-S17: outcome: rates of interval cancers

Resources to support providers and commissioners

Additional BSP operational guidance is included in the:

• service specifications

• professional guidance

• education and training guidance

Reporting and publishing standards

We publish annual standards and quarterly KPI data. We share the data with NHS England and NHS Improvement before publication.

When data is reviewed, we recommend that several of the standards are examined together to build a picture of performance.

Standard BSP-S07 (rate of referral to assessment) should be reviewed together with BSP-S13 (positive predictive value) and BSP-S16 (non-invasive cancer detection rates) to make sure that both screening specificity and sensitivity are maximised.

Standard BSP-S14 (age standardised detection ratios for invasive cancers) should be looked at in conjunction with BSP-S04 (screening round length), BSP-S13 (positive predictive value of referral) and BSP-S07 (rate of referral to assessment).

Standard BSP-S17 (rates of interval cancers) should be looked at in conjunction with BSP-S13 (positive predictive value of referral). A very high positive predictive value may indicate that the service is only recalling the obvious cancers and are missing smaller cancers which go on to present as interval cancers.