OpenSAFELY Service Restoration Observatory: Eleven key measures for monitoring general practice clinical activity during COVID-19

This report accompanies this preprint, describing trends and variation in clinical activity codes using a set of key measures indicative of overall activity to evaluate NHS service restoration throughout the COVID-19 pandemic, using federated analytics on 48 million adults’ primary care records through OpenSAFELY. We will provide regularly updated results in a separate report

The aim of the OpenSAFELY SRO is to describe trends and variation in clinical activity codes to evaluate NHS service restoration during the COVID-19 pandemic.

This report provides a set of key measures of general practice activity, that are indicative of changes in overall activity throughout the COVID-19 pandemic. These key measures were selected from a range of clinical areas, prioritising clinical topics that would benefit from routine monitoring and targeted action considering the following criteria: high volume usage, clinically relevant to front-line practice and whether they are more widely indicative of other problems in service delivery across the NHS (for example a decrease in records for blood tests for kidney function may be a true drop in GPs requesting these tests or it may be related to delays in laboratories processing the results).

For each of these measures we provide a link to the codelist containing all the codes used for that measure, a description of what the measure is and a brief overview of why the measure is important. We also highlight any caveats, where there are any, for each measure. For each measure we also indicate the number of unique patients recorded as having at least one event indicated by the measure as well as the total number of events since January 2019.

Monthly rates of recorded activity are displayed as practice level decile charts to show both the general trend and practice level variation in activity changes. Accompanying each chart is a summary of the most commonly recorded SNOMED-CT codes for each measure. Using the rate in April 2019 as a baseline, we calculate the percentage change from baseline in April 2020 (1st national lockdown) and April 2021. These changes are used to give an overall classification of activity change as described in the box below.

• No change: no change from baseline in both April 2020 and April 2021.
• Increase: an increase from baseline in either April 2020 or April 2021.
• Sustained drop: a drop from baseline of >15% in April 2020 which has not returned to within 15% of the baseline by April 2021.
• Recovery: a drop of >15% from baseline in April 2020 which has returned to within 15% of the baseline by April 2021.

Summary of results

These key measures demonstrated substantial changes in clinical activity throughout the COVID-19 pandemic. Six of the measures recovered to their pre-pandemic baseline within a year of the pandemic, showing a rapid, adaptive response by primary care in the midst of a global health pandemic. The remaining five measures showed a more sustained drop in activity; asthma and COPD reviews did not recover to their pre-pandemic baseline until around August 2021 and blood pressure monitoring, cardiovascular disease risk assessment and medication reviews had a sustained drop in activity that persisted up to December 2021.

Findings in context

Discussion of the specific causes and reasons for the changes in narrow measures of clinical activity we have described is best addressed through quantitative analyses that identify practices in high and low deciles to approach for targeted qualitative interviews with patients and front line staff. However we believe the following broad points may help aid interpretation. Our measures reflect only a few areas of high volume clinical activity; decreases may reflect appropriate prioritisation of other clinical activity. For example NHS Health Checks, which are used to detect early signs of high blood pressure, heart disease or type 2 diabetes, were paused during the pandemic; this is likely to explain the sustained drop in activity in cardiovascular disease risk assessment and blood pressure monitoring. However, in specific cases this may reflect changes in the style of delivery of a clinical activity, rather than the volume: for example, where patients record their own blood pressure at home since, as we have previously highlighted, home monitoring of blood pressure may not be recorded completely or consistently in GP records. In addition, not all reductions should be interpreted as problematic: as part of the COVID-19 recovery, health systems are aiming to be more resilient, responsive and sustainable; complete recovery may not always be appropriate and reductions in clinical activity across some domains may reflect rational reprioritisation of activity. Where these changes in priority have not been nationally planned, data analyses such as ours may help to rapidly identify the pragmatic changes in prioritisation being made by individual dispersed organisations or people across the healthcare ecosystem before those changes are explicitly surfaced or discussed through other mechanisms. For more detail, please see our preprint here

The following key measures are provided:

• Blood Pressure Monitoring
• Cardiovascular Disease 10 Year Risk Assessment
• Cholesterol Testing
• Liver Function Testing - Alanine Transferaminase (ALT)
• Thyroid Testing
• Full Blood Count - Red Blood Cell (RBC) Testing
• Glycated Haemoglobin A1c Level (HbA1c)
• Renal Function Assessment - Sodium Testing
• Asthma Reviews
• Chronic Obstrutive Pulmonary Disease (COPD) Reviews
• Medication Review

Blood Pressure Monitoring¶

The codes used for this measure are available in this codelist.

What is it and why does it matter?

A commonly-used assessment used to identify patients with hypertension or to ensure optimal treatment for those with known hypertension. This helps ensure appropriate treatment, with the aim of reducing long term risks of complications from hypertension such as stroke, myocardial infarction and kidney disease.

Caveats

We use codes which represent results reported to GPs so tests requested but not yet reported are not included. Only test results returned to GPs are included, which will usually exclude tests requested while a person is in hospital and other settings like a private clinic.

Cardiovascular Disease 10 year Risk Assessment¶

The codes used for this measure are available in this codelist.

What is it and why does it matter?

A commonly-used risk assessment used to identify patients with an increased risk of cardiovascular events in the next 10 years. This helps ensure appropriate treatment, with the aim of reducing long term risks of complications such as stroke or myocardial infarction.

Cholesterol Testing¶

The codes used for this measure are available in this codelist.

What is it and why does it matter?

A commonly-used blood test used as part of a routine cardiovascular disease 10 year risk assessment and also to identify patients with lipid disorders (e.g. familial hypercholesterolaemia). This helps ensure appropriate treatment, with the aim of reducing long term risks of complications such as stroke or myocardial infarction.

Caveats

We use codes which represent results reported to GPs so tests requested but not yet reported are not included. Only test results returned to GPs are included, which will usually exclude tests requested while a person is in hospital and other settings like a private clinic.

Liver Function Testing - Alanine Transferaminase (ALT)¶

The codes used for this measure are available in this codelist.

What is it and why does it matter?

An ALT blood test is one of a group of liver function tests (LFTs) which are used to detect problems with the function of the liver. It is often used to monitor patients on medications which may affect the liver or which rely on the liver to break them down within the body. They are also tested for patients with known or suspected liver dysfunction.

Caveats

In a small number of places, an ALT test may NOT be included within a liver function test. We use codes which represent results reported to GPs so tests requested but not yet reported are not included. Only tests results returned to GPs are included, which will usually exclude tests requested while a person is in hospital and other settings like a private clinic.

Thyroid Testing¶

The codes used for this measure are available in this codelist.

What is it and why does it matter?

TSH is used for the diagnosis and monitoring of hypothyroidism and hyperthyroidism, including making changes to thyroid replacement therapy dosing.

Caveats

We use codes which represent results reported to GPs so tests requested but not yet reported are not included. Only test results returned to GPs are included, which will usually exclude tests requested while a person is in hospital and other settings like a private clinic.

Full Blood Count - Red Blood Cell (RBC) Testing¶

The codes used for this measure are available in this codelist.

What is it and why does it matter?

RBC is completed as part of a group of tests referred to as a full blood count (FBC), used to detect a variety of disorders of the blood, such as anaemia and infection.

Caveats

Here, we use codes which represent results reported to GPs, so tests requested but not yet reported are not included. This will usually exclude tests requested while a person is in hospital and other settings, like a private clinic.