There are 6976 Data Zones in Scotland. Data Zones are:
“the core geography for making available small area statistics across most social topics including information about benefits, education, health and the labour market.”
They allow users to:
“readily (and regularly) bring together information from various sources on a common small area geography.”
Purpose of Data Zones
Data Zones were developed to inform the approach to delivering services and improving quality of life.
They can be used to definitively identify and agree which areas have the greatest need and understand the different needs of deprived, rural and remote local areas.
Data Zones are also used to:
– Support national and local policy making in a joined-up way.
– Allocate resources and develop targets across the public sector.
– Examine the impact of policies.
– Examine the progress made against both local and national commitments and targets.
Coverage, shape and size of Data Zones
Data Zones are a set of adjoining polygons with centroids that cover the whole of Scotland.
Starting with school catchment areas, groups of complete Census Output Areas (COA) were brought together to form individual Data Zone boundaries that also respect physical boundaries and other boundaries of local significance.
The resultant compact shape of Data Zones makes them significantly smaller than previous geographies for which statistics have been available (postcode sector or ward). Furthermore, the shape is considered ‘stable’ (does not often change) and doughnut shaped data zones are permitted but avoided.
The area of each Data Zone is calculated in hectares and square kilometres from the COAs, using the Office of National Statistics (ONS) standard area measurement methodology. Urban area Data Zones can be very small in size, whereas in rural areas they can cover large areas.
Data Zones nest inside council area boundaries and other administrative geographies either via look ups (2001 and 2011) or best-fit matrixes.
Releases of Data Zones
There have been two releases of Scottish Data Zones, each approximately three years after a census:
| Release Name | Release Date | Format | Number |
|---|---|---|---|
| Data Zone 2001 | Spring 2004 | Boundaries Centroids | 6505 |
| Data Zone 2011 | 6th November 2014 | Boundaries Centroids | 6976 |
The changes in Data Zone number, shape and size between releases are due to changes in population caused by housing demolition and development as well as the difference between 2001 to 2011 COAs and postcode boundaries. Guidance and a look up spreadsheet exists for matching Data Zones between releases.
Household, resident and total populations
The 2011 Data Zone release (boundaries and centroids) contains population estimate information derived from the 2011 census. There are three different population types.
| Population Type | Attribute Name | Definition |
|---|---|---|
| Household | HHCnt2011 | Number of people living in households on the night of the 2011 census |
| Resident | ResPop2011 | Number of people usually resident in a household in the Data Zone. As opposed to where they were on the night of the 2011 census |
| Total | TotPop2011 | Includes people usually resident in a communal establishment in the Data Zone. As opposed to where they were on the night of the 2011 census |
The map below highlights Data Zones which have and don’t have any communal establishment residents.
Each Data Zone consists of approximately equal resident populations of 500 to 1000 people, with an absolute minimum of 375 people and a maximum population of 1125.
However, 26 Data Zones of the 2011 release do not comply with this resident population size requirement. Eleven have less than 375 and five have greater than 1125.
Communities and neighbourhoods
Data Zones consist of households with similar social characteristics (derived using the Townsend Index of Deprivation as a measure of social homogeneity) and where possible Data Zones relate to some community of interest, but they do not necessarily delineate communities on the ground.
In addition, Data Zones are effective in identifying small areas with particular social characteristics whilst being large enough to protect confidentiality. Where the release of potentially sensitive data at the Data Zone level may prove to be disclosive, Data Zones can be aggregated into a composite geography called Intermediate Zones. For example, Intermediate Zones (as a proxy for neighbourhoods) were used in a recent BBC article on how communities have been impacted by COVID-19.
Community Planning Partnerships have been specifically identified as benefiting from the use of Data Zones. An aim of ‘Commitment 3: Improving how data is shared’ of the Scotland’s Open Government Action Plan for 2018-20 is:
“To better understand Scotland’s communities, we will increase the number of datasets that provide information at a local level. We will promote the use of this information in local area profiles to aid local decision-making.”
and is to be achieved by:
“Increasing the number of datasets available for small areas (such as data zone and intermediate zone levels)”
Community attitudes and allegiances were considered only through the local authority input during this initial Data Zone design process.
Data Zone names and codes
The 2001 Data Zone release did not assign names to all Data Zones.
“It is impractical to develop a set of names for zones with a household population as small as 500-1000 in urban areas, and hence codes were used”
In the 2011 Data Zone release most data zones have been named according to the Intermediate Zone in which they reside, following the format ‘Intermediate Zone Name – 01’, ‘Intermediate Zone Name – 02’, etc.
– East Lothian and West Dunbartonshire us the Intermediate Zone number instead of name
– Fife and Scottish Borders Councils have given names to each Data Zone
A report in support of Moray Community Engagement Group’s proposal to have locally relevant names for Data and Intermediate Zones in Moray seems not to have been progressed.
Data and Intermediate Zones have the Government Statistical Service (GSS) code prefix of S01 and S02 respectively.
Data Zone design process
The Data Zone design process started in 2001. It involved Scottish Government, the School of Geography and Sustainable Development at St Andrew’s University and a stakeholder group (the Scottish Neighbourhood Statistics Neighbourhood Definitions Group).
Over the following two years split into four stages (stage A, stage B and stage C/D), Data Zone production strategies and prototypes were developed prior to a seminar in Glasgow at the end of 2002 and the first Data Zone release in 2004.
In 2010 and 2013 Scottish Government also consulted before the 2011 Data Zone release in 2014.
Evaluation of Data Zones
2011 – Data Zones were evaluated to investigate how demographic changes, boundary issues and loss of social homogeneity has effected the stability of Data Zones as a geographic unit over time.
2014 – The Research Excellence Framework Impact Case Studies produced a report on the construction and adoption of data zones as a new geography of Scotland.
2015 – The National Registers of Scotland evaluated the accuracy of population estimates for non-standard geographical areas built up from 2001 and 2011 Data Zones.
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