Cervical Screening Programme, England - 2019-20 [NS]

Coverage is defined as the percentage of women in a population who were eligible for screening at a given point in time (31 March 2020 in this instance) and who were screened adequately within a specified period.

Women are identified as eligible for screening if they are:

• registered with a GP (or otherwise know to the NHS)
• in the screening age range (25 to 64 years)
• not ineligible because their recall has been ceased for clinical reasons (most commonly due to hysterectomy)

As the frequency with which women are invited for screening is dependent on age, coverage is calculated differently for different age groups.

For the total target age group (25 to 64 years), coverage is presented in this report, which represents the most up to date definition¹.

This takes into account the frequency with which women of different ages are invited for screening.

Women aged 25 to 49

Women aged 50 to 64

Women aged 25 to 64

Coverage statistics in this report are calculated using data from the National Health Application and Infrastructure Services (NHAIS) system via Open Exeter and include all women registered with an NHS GP practice and those who are not registered with a GP practice but who are otherwise known to the NHS.

The total number of women who are not registered with a GP or otherwise known to the NHS is not recorded. It is therefore not possible to estimate how overall coverage rates might be affected by this group.

NHAIS data supports many primary care services including the NHS Cervical Screening Programme’s call and recall system for inviting women for screening. NHAIS is the only data source that can identify both the eligible population and those women who have been tested in the last 3 or 5 years.

Coverage at LA level is based on the eligible LA resident population.  Coverage at Primary Care Organisation (PCO) level, i.e. prior to 2013-14, was based on the eligible PCO responsible population.

For more information on the difference between LA resident and PCO responsible populations see the ‘Impact of NHS reorganisation’ section of the data quality statement.

Achievable standards for laboratory reporting in cervical screening are set for key indicators². See the main report for current data relating to these standards.

Positive predictive value (PPV) is the proportion of women referred with high-grade abnormalities who have a histological outcome of cervical intraepithelial neoplasia (CIN)2, CIN3, adenocarcinoma in situ/cervical glandular intraepithelial neoplasia (CGIN) or cervical cancer.

PPV is calculated from outcomes of referral for tests with results of high-grade dyskaryosis (moderate) or worse as follows:

(Numerator / Denominator) x 100

Numerator
Number of women referred to colposcopy in the previous 12 months with a cytology result of moderate dyskaryosis or worse, whose colposcopic outcome is a histological diagnosis of CIN2, CIN3, adenocarcinoma in situ/CGIN or cervical cancer.

Denominator
Number of women referred to colposcopy in the previous 12 months with a cytology result of moderate dyskaryosis or worse, whose colposcopic outcome is no abnormality detected (NAD) or a histological diagnosis of normal, HPV, CIN1 or worse.

CIN1 or worse is defined as: CIN1, CIN2, CIN3 adenocarcinoma-in-situ/CGIN or cervical cancer.

Abnormal predictive value (APV) is the percentage of samples reported as borderline or low-grade which lead to a colposcopy referral and where the histological outcome is CIN2, CIN3, adenocarcinoma in situ/CGIN or cervical cancer.

APV is calculated from outcomes of referral for tests with results of borderline or low-grade dyskaryosis as follows:

(Numerator / Denominator) x 100

Numerator
Number of women referred to colposcopy in the previous 12 months with a cytology result of borderline or low-grade dyskaryosis whose colposcopic outcome is CIN2, CIN3, adenocarcinoma in situ/CGIN or cervical cancer.

Denominator
The number of women referred to colposcopy in the previous 12 months with cytology result of borderline or low-grade dyskaryosis whose colposcopic outcome is colposcopy NAD or a histological diagnosis of normal, HPV, CIN1 or worse.

Referral Value (RV) is defined as the number of women referred to colposcopy (excluding inadequate referrals) per detection of one CIN2 or worse lesion and is defined as follows:

(Numerator / Denominator)

Numerator
Number of women referred with all results except inadequate with outcome of referral: cervical cancer, adenocarcinoma in situ/CGIN, CIN3, CIN2, CIN1, HPV only, no CIN/HPV, seen but no abnormality detected/no biopsy taken.

Denominator
Number of tests as per numerator, but only including outcome of referral: cervical cancer, adenocarcinoma in situ/CGIN, CIN3 or CIN2.

From April 2013, RV excludes women referred to gynaecology following a test result of ?glandular neoplasia (non-cervical).

Women with negative cytology but who test positive for HPV and are referred to colposcopy are not currently included in the calculation of referral value.

A percentile is the value of a variable below which a certain percent of observations fall.

For example, the 10th percentile is the value (or score) below which 10 percent of the observations may be found.

Definitions of clinical terminology used in this report are provided below - click on a letter to see all terms beginning with that letter.

For definitions of further medical terminology not covered below please visit the NHS Cancer Screening Programmes website.

1. See http://www.phoutcomes.info/ and https://www.gov.uk/government/publications/healthy-lives-healthy-people-improving-outcomes-and-supporting-transparency for more information.
2. For more information see: https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/436753/nhscsp01.pdf