On Monday 16 March 2020, the UK government announced a package of measures, advising those who are or may be at increased risk of severe illness from COVID-19 to be particularly stringent in following social distancing measures. NHS Digital established the first iteration of the NHS Shielded Patient List using Hospital Episode Statistics (HES) data. On 6 April 2020, NHS Digital reviewed if a GP feed could be implemented daily. After engaging with suppliers and Government Digital Service (as the downstream recipients) it was agreed that the feed would remain weekly, with this delivered in SPL2.

SPL2 added data extracting from GP systems using the GP Extract Service (GPES). GP data is coded in SNOMED CT, which allows the identification of individual conditions, and was taken from the systems themselves so accurate at the time of extraction. The results of SPL1 and 2 were uploaded to GP systems, adding a high-risk flag against the patient records. 

NHS England requested that GPs and hospital Trusts review and add to the NHS Shielded Patient List to ensure that patients were not incorrectly added or excluded by the national algorithm. GPs were asked to:

• review the national list and remove patients incorrectly added – 14 April 2020
• review patients added by hospital Trusts – ongoing
• add high risk flags for individual who should be on the list but not picked up by the national algorithm – 14 April 2020
• review individuals who have self-identified as vulnerable – 17 April 2020

The results of the first three requests were captured in SPL3 and (if occurred after the deadline) SPL4+5. SPL3 was the first release that included GP and hospital additions.

SPL4+5 became a combined release covering 2 weeks of activity. It also included GP deductions for the first time. This is where a patient is removed from the NHS SPL at the request of a GP practice. They do this by setting a low or moderate risk flag on the patient’s record.  

SPL6 used updated files from the primary care medicines and maternity services datasets to inform the national algorithm. It also included dialysis patients although as the attached spreadsheet shows, not all Trusts have submitted since the request was issued at the end of April.

SPL7 was a routine run containing most of the remaining Trust dialysis patients. The Trusts who had not submitted data were flagged for follow up by NHS England. SPL7 also included a small number of hospital deductions for the first time.

SPL8 was a routine run with no new changes from a data perspective. Communication from SPL8 for nationally added patients was paused as the future of the shielding programme was being reviewed. The communications were released (letters only) on Thursday 4 June. SMS texts messages were not reinstated as the decision was taken to only use letters for the policy update at the end of May.

SPL9 incorporated both GP and NHS Business Services Authority (NHS BSA) medication data to ensure that the algorithm used the timeliest information. GP meds data is kept up to date weekly whilst NHS BSA data lags a few months. Communication from SPL9 for nationally added patients was paused as the future of the shielding programme was being reviewed. The communications (letters only) were released on Thursday 4 June.

Following SPL9, the shielded patient list entered a steady state.