The utility of anonymised postcoded registration data provided by the Dental Practice Board

Area of Science:

• Dental Public Health
• Health Informatics
• Geographic Information Systems (GIS)

Background:

• Accurate patient location data is crucial for public health planning and resource allocation.
• The Dental Practice Board (DPB) holds registration data that could inform dental service commissioning.
• Assessing the quality of postcode data within the DPB is essential for its utility.

Purpose of the Study:

• To evaluate the completeness of postcode data held by the DPB.
• To assess the accuracy of using dental practice location as a proxy for patient residential address.
• To determine the feasibility of using DPB data for small-area analysis.

Main Methods:

• Cross-sectional evaluation of anonymised DPB registration data for children under 6 in North West England.
• Calculation of the geo-referencing success rate for postcodes within DPB datasets.
• Determination of the proportion of children residing in the same health authority as their registered dental practice.

Main Results:

• Only 60.8% of 193,466 child registrations in the North West could be geo-referenced due to incomplete postcode data.
• Significant regional variation in postcode data completeness was observed.
• While most children lived in the same health authority as their practice, 28.5% registered in Manchester Health Authority were not Manchester residents.

Conclusions:

• Incomplete postcode data in DPB datasets prevents accurate small-area registration rate calculations.
• Using dental practice location as a proxy for residential address is inaccurate, particularly in large urban areas.
• Resolving poor postcode coverage is necessary for DPB data to be valuable for health commissioners.