1. Main findings
Just over 17,000 or 13.5% of shielded patients do not have access to a private outdoor space, compared with 105,000 (82.6%) who do. For 5,000 shielded patients (3.9%) it is unclear whether they have access to private outdoor space as their data could not be linked.
A higher percentage of households with a shielded patient resident (‘shielded households’) have access to a private outdoor space (85.8%) than the Welsh average (80.3%). This is also true for each Welsh local authority.
The linking match rate for the Shielded Patient List to Ordnance Survey (OS) green spaces data was 96.1%. The remaining 3.9% of shielded patient records did not match to the OS data.
2. Shielded individuals by local authority
The percentage of individuals with access to a private outdoor space varies by local authority, with Rhondda Cynon Taf and Merthyr Tydfil having the highest (87.8% and 87.7%) and Conwy and Cardiff having the lowest (76.4% and 77.1%).
We could not link a small percentage of shielded patients to private outdoor space access data. They are shown in chart 2 below in a separate category.
3. Household access to private outdoor space by local authority
The percentage of households with access to private outdoor space varies by local authority. In each local authority, the percentage of shielded households with access to a private outdoor space is higher than for all households.
Shielded households differ from shielded individuals because a household may have more than one shielded patient living there. Shielded patients with unknown access to private outdoor space are not included in the figures below as it was not possible to work out whether they lived with another shielded patient.
4. Quality and methodology information
The Administrative Data Research Unit (ADRU) in Welsh Government undertakes various data linking analyses, including those related to the COVID-19 pandemic. For this analysis, the Ordnance Survey Green spaces data on access to private outdoor spaces was linked to the Shielded Patient List in Wales to estimate the percentage of shielded households and individuals that do and do not have access to private outdoor spaces
Ordnance survey data on green spaces contains information on private outdoor space presence or absence for residential addresses. Topographic area baseline data from 14/08/2019 was used to derive areas containing at least one building and one residential garden feature, and was linked to address records to produce this data.
The Shielded Patient List is derived using a variety of data sources drawn from the Health Service. It contains information on living patients classed as ‘high risk’ during the coronavirus pandemic and who were initially advised to shield for 12 weeks. This analysis used the Shielded Patient List for Wales as at 15/06/2020. The data owners are NHS Wales Informatics Service (NWIS), and Unique Property Reference Number (UPRN) data based on address information was added by the Newport Information Hub. More information on the sources and methodology can be accessed on the NHS Wales Informatics Service.
We linked the Shielded Patient List and Ordnance Survey Green spaces data sets using SQL to join the data sets on the Unique Property Reference Number (UPRN). We broke the results down by local authority, residence type and private outdoor space availability. A small number of shielded patients were registered at residences outside Wales and were removed from the results and further analysis. Duplicate NHS numbers were also removed.
For the purposes of this analysis, where the Ordnance Survey data indicated the property is a flat, we assumed the private outdoor space availability to be ‘no’, because automating the derivation of sites for flats is more susceptible to error than for houses. However, this is not perfect as many flats will have balconies (although these are likely to offer limited opportunities for exercise) and some will have access to a private garden.
Where a UPRN on the Shielded Patient List was missing or did not match to a UPRN on the green spaces data set, it was not possible to include the records in the household level analysis, as it was not possible to assess which patients may be living in the same residence.
It is not yet clear how care homes, prisons and other institutions may be affecting these results.
This research has been carried out as part of the ADR Wales programme of work. The ADR Wales programme of work is aligned to the priority themes as identified in the Welsh Government’s national strategy: Prosperity for All. ADR Wales brings together data science experts at Swansea University Medical School, staff from the Wales Institute of Social and Economic Research, Data and Methods (WISERD) at Cardiff University and specialist teams within the Welsh Government to develop new evidence which supports Prosperity for All by using the SAIL Databank at Swansea University, to link and analyse anonymised data. ADR Wales is part of the Economic and Social Research Council (part of UK Research and Innovation) funded ADR UK (grant ES/S007393/1).