Accredited official statistics

Data quality statement

Published 9 December 2025

Applies to England

Introduction and background

This document is a background quality report for the adult oral health survey (AOHS) 2023. It provides a summary of the main quality-related matters that users of the survey need to be aware of. A more detailed discussion of the survey methodology and how it affects quality is provided in the technical report published alongside this report.

This report is aligned to the UK Statistics Authority’s Code of Practice for Statistics and official guidance on Quality statistics in government. It also covers the European Statistical Service’s dimensions of quality, which form principles 11 to 15 of the European Statistics Code of Practice. These principles are:

• relevance
• accuracy and reliability
• timeliness and punctuality
• coherence and comparability of the survey over time
• accessibility and clarity

The AOHS 2023 was carried out from June 2023 to April 2024 with a representative sample of adults in England aged 16 and over. The survey was commissioned by the Office for Health Improvement and Disparities (OHID) within the Department of Health and Social Care (DHSC). The survey was carried out by a consortium led by the National Centre for Social Research (NatCen), and includes:

• Department of Dentistry at the University of Birmingham
• Faculty of Dentistry, Oral and Craniofacial Sciences at King’s College London
• School of Dental Sciences at Newcastle University
• Dental Public Health Group at the Department of Epidemiology and Public Health at University College London
• Office for National Statistics

The University of Leeds also provided guidance and support to the survey and its design.

The AOHS is the latest in a series of nationally representative surveys of adults’ oral and dental health in England, carried out between 1968 and 2009. These surveys, previously known as adult dental health surveys (ADHSs), have been used to estimate the prevalence of dental and oral health conditions. In addition, this survey has collected data on the following areas:

• associated behaviours, including service use
• the impact of poor oral and dental health
• barriers to accessing care

The AOHS was initially commissioned in early 2020 and included the proposal to rename the survey as the adult oral health survey, to reflect its scope and contents. At that time, it was expected that the survey would follow closely the design of previous ADHSs, including a face-to-face interview and an oral examination. By late 2020, when data collection was commissioned, the progress of the COVID-19 pandemic meant that this was not feasible at that time. Consequently, the AOHS 2021 was carried out as an online and paper survey with no oral examination, thereby sitting outside the regular AOHS series. Due to this, the AOHS 2021 has not been included in any of the trends over time analysis.

The AOHS 2023 was commissioned in 2022 and reverted to the design of previous ADHSs, where participants took part in a face-to-face interview and an oral examination. It was decided to combine the data collection into one in-person visit (rather than 2 separate visits which was done in the past).

The survey findings are published as reports and data tables.

Assessment of statistics against quality dimensions and principles

Relevance

This dimension covers the degree to which the statistical product meets user needs in both coverage and content.

The AOHS 2023 was designed as a continuation of the national ADHS series that has been carried out approximately every 10 years since 1968. Like the most recent previous survey (the ADHS 2009), the AOHS covered the following areas:

• general health
• behaviours related to oral health, including oral hygiene
• oral health (health of teeth and gums)
• use of dental services
• barriers to dental attendance
• impacts of oral health problems
• presence, number and condition of teeth
• prevalence of tooth decay
• prevalence of restorations and types of restorations
• prevalence of oral health conditions
• trends and comparisons over time

A comprehensive stakeholder consultation was undertaken between March and April 2020 to inform survey content for the 2021 survey and to understand the needs of users. The following stakeholder groups were included:

• Public Health England (central team, consultants and trainees)
• NHS (NHS England commissioners, consultants and specialists)
• British Dental Association
• Faculty of Dental Surgery
• Faculty of General Dental Practice
• Health Education England
• general dental services
• community dental services
• third sector organisations
• academia (in the UK and internationally)
• scientific societies

The aims of the consultation were to generate views on:

• the survey design and protocols, and applications of previous data
• the most relevant information to collect and main priority areas for questionnaire and oral examination content
• potential areas for innovation (such as new content and methodological areas)

Overall, 89 individuals and organisations contributed their views to the stakeholder consultation, which highlighted the importance of the survey and identified priority areas of interest. Contributions were received as follows:

• a total of 52 individuals took part during the 4 stakeholder consultation events
• there were 8 individuals who contributed through individual remote meetings and email communication
• input through the online survey questionnaire was provided by 29 individuals or organisations

Decisions for the 2021 online questionnaire (which the 2023 questionnaire was largely based on) as well as the 2023 oral examination, were founded on outcomes from this consultation process. Important decision areas included that: 

• data collected in the oral examination should be retained to ensure continuity with the 2009 ADHS as a priority, to allow for the comparisons for trends in oral diseases and conditions while also reflecting changes in the understanding of the evidence around oral health and innovations that had been made in the interim in both clinical practice and policy
• the sample should be of sufficient size to enable analysis of subgroups according to main demographic indicators (for example, age, sex and socioeconomic status) and geographical characteristics (for example, NHS regions and Index of Multiple Deprivation (IMD))
• recruitment of the examiner workforce include foundation dentists and dental public health specialty trainees, supplemented by dental therapists and hygienists. These changes reflected widespread advice from the consultations that the previous model of examiner recruitment was no longer feasible (as the previous community dental service that had supplied examiners in earlier ADHSs had different commissioned arrangements)

Some important differences were made to the 2023 oral examination to reflect the changes and innovations that have been made in both clinical practice and policy. These were:

• tooth condition: codes for visual and cavitated enamel caries were included in 2023 in addition to codes for caries into dentine and pulp (following the same innovation that was adopted in the 2013 Child Dental Health Survey). To conduct comparisons with the 2009 ADHS, data was also recoded to 2009 criteria
• the 2009 criteria for tooth wear, which focused on the condition of anterior teeth only, was replaced by the Basic Erosive Wear Examination (BEWE) Index (that records wear in all teeth by sextant) which had been successfully trialled in some areas in 2009
• periodontal condition criteria were revised in line with the 2017 internationally agreed classification, that is, the presence of obvious interdental recession was added and loss of attachment was recorded for all age groups. To conduct comparisons with the 2009 ADHS, data was also recoded to 2009 criteria

As well as revisions to the oral examination content, the consultation highlighted priority areas for questionnaire content. These included a reduction of questions evaluating the dentist and dental practice at last visit and expanding questions on treatment choices and cost. This was reflected in the 2021 survey content which the 2023 survey was based on. Further differences between the 2023 survey content and 2021 survey content were agreed with OHID.

To access a full summary of the findings from the 2020 stakeholder consultation, email dentalphintelligence@dhsc.gov.uk.

Accuracy and reliability

This dimension covers, with respect to the statistics, the proximity between an estimate and the unknown true value. Accuracy of the statistics means estimating and reporting uncertainty.

Surveys gather information from a sample rather than from the whole population. Results from sample surveys are estimates, not exact numbers.

The precision of survey estimates is dependent on the number of people in the sample on which the survey is based. The larger the sample, the more precise the estimates, and, conversely, estimates based on smaller samples are less precise and more variable. Estimates for small groups are less reliable and tend to be more unpredictable than for larger aggregated groups.

Survey estimates are subject to sampling error. The AOHS 2023 used a clustered, stratified multi-stage sample design and, in addition, weights were applied when producing survey estimates. One of the effects of using the complex design and weighting is that standard errors for survey estimates are generally higher than the standard errors that would be derived from an unweighted simple random sample of the same size. The statistical significance of differences between groups mentioned within the survey reports have taken into account the clustering, stratification and weighting of the data. Differences between estimates have not been commented on unless they are significant at the 95% confidence level, meaning that there is less than 5% probability that the observed difference could be due to random sampling variation when no difference occurred in the population from which the sample is drawn.

In common with previous ADHSs, the AOHS 2023 was based on a multi-stage stratified probability sample design. The sample was provided by the Office for National Statistics and was drawn from the AddressBase Premium database. This database combines data from local authorities, Royal Mail and Ordnance Survey, and enables more accurate identification of residential units than the Postcode Address File (PAF) used in previous ADHSs.

The sample was designed to be representative of adults aged 16 and over living in private households in England. The sample excludes people living in institutional settings (for example, students in halls of residence, adults in care homes and prisoners) and temporary housing (for example, hostels and bed and breakfast accommodation), as well as people sleeping rough. It is likely that the oral health of these groups varies from people in private households, but these groups make up a small proportion of the adult population and their exclusion is unlikely to have a noticeable effect on survey estimates.

A household response rate of 28% was achieved. In total, productive responses were received from 2,285 individuals. Of those individuals, 1,619 (71%) oral examinations were also achieved. Details of the sample design and survey methods are published in the technical report.

Data and published findings have been quality assured at each stage of production. The checks applied are described in the technical report.

Timeliness and punctuality

Timeliness refers to the time gap between publication and the reference period. Punctuality refers to the gap between planned and actual publication dates.

The original plan for publication was by the summer of 2024. However, there were delays due to both fieldwork and data processing. Recruitment of dental examiners was more difficult than expected, meaning that not enough examiners were available to cover the work during the originally planned fieldwork period. As a result, further recruitment and training rounds were undertaken, and a longer fieldwork period was needed to cover the selected sample. There were also delays in checking, cleaning and processing the complex data required for the analysis. The survey data was processed and validated in the summer of 2024. This publication was released on the planned and pre-announced publication date.

Comparability and coherence 

Comparability is the degree to which data from specific populations can be compared over time. Coherence is the degree to which data which has been derived from different sources or methods but refer to the same topic are similar.

The AOHS 2023 was designed so that the main elements would be comparable with the 5 previous ADHSs carried out between 1968 and 2009 while also reflecting the innovations required to accommodate the changes in our understanding of oral health and its measurement over the 14 year period and COVID-19 pandemic. The populations covered by these surveys have varied over time. All previous surveys covered England and Wales. Scotland and Northern Ireland were also covered in some but not all of those surveys. The 2023 survey covered England only.

Since the 2009 survey, the different nations have carried out their own adult oral health surveys using varying scopes, age ranges and methodologies. Scotland published an adult oral health survey for 2016 to 2018 in 2019. This included the results of 2 dental surveys undertaken in dental practices. In 2020, the Welsh dental survey of 18 to 25 year olds was published. This reported on the oral health of young adults attending a range of purposively selected community settings from 2017 to 2019. In 2022 Ireland published An Overview of Dental Services and Oral Health in Northern Ireland and Ireland but no new oral health data for adults was presented. Due to the different methods used in these surveys, the results are not comparable with the results of AOHS 2023 or previous ADHSs.

The AOHS 2023 sample design was consistent with previous ADHSs - a multi-stage stratified probability sample of private addresses. The household response rate achieved (28%) was lower than in past surveys. However, this is consistent with broader trends in survey response rates (for example, the Family Resources Survey 2022 to 2023 achieved a response rate of 25% and the English Housing Survey 2022 to 2023 achieved a response rate of 32%). As in previous surveys, the data was weighted to make it representative of the adult population of England, which will reduce the risk of bias stemming from the lower response rate.

There are 2 main differences to be aware of:

• the 2023 survey covered England only for the first time. Previous ADHSs have covered England and other nations of the United Kingdom and this has varied in each of the survey years
• in previous ADHSs data collection involved a 2-stage approach - an in-person visit followed by an oral examination. The 2023 survey fieldwork model was designed to collect data during on in-person visit with an interviewer and dental examiner present at the same time

Where any caveats in the comparison of the 2023 findings with previous ADHSs are required, these have been made clear in the report. Due to differences in survey methodology (as a result of the COVID-19 pandemic), comparisons with the 2021 survey were not possible.

Accessibility and clarity

As described in Understanding accessibility requirements for public sector bodies, accessibility means “making your content and design clear and simple enough so that most people can use it without needing to adapt it, while supporting those who do need to adapt things.”

Clarity refers to the quality and sufficiency of the metadata, illustrations and accompanying advice.

Reports of findings are published in HTML format. They are written in accessible language and illustrated with charts. The tables are published in ODS format. Text, charts and tables have been produced in line with the government accessibility guidelines. 

Detailed metadata is published in the technical report.

Quality assurance by the Office for Health Improvement and Disparities

In addition to the quality assurance checks described above that were undertaken by the consortium led by NatCen, additional quality assurance checks were undertaken at various stages of the survey by OHID within DHSC, the government department that published the survey.

Survey materials prior to fieldwork

OHID checked copies of the advance letters and other materials used in the survey. This was to ensure they were free from error and met their requirements. Checks included a 2-stage process whereby a consultant in dental public health (and national lead in dental epidemiology) from OHID and a professor of dental public health from the University of Leeds independently reviewed all survey materials against the scope of the project.

Questionnaire and oral examination

OHID reviewed the questionnaire and oral examination documentation, including checking the question routing, question text and response codes.

Training and calibrating

OHID reviewed the training materials used for the interviewers and dental examiners. All changes between the pilot and mainstage training and fieldwork were agreed with OHID. OHID also attended a mainstage training event held in London.

Fieldwork monitoring

During the fieldwork period, OHID monitored the progress of the survey on a weekly basis. This included reviewing the response rates both at national and NHS England region level. This was important, because low response rates can limit the representativeness, and therefore usability, of the data.

Approval for publication

As a final stage, a consultant in dental public health (and national lead in dental epidemiology) at OHID and a professor of dental public health from the University of Leeds reviewed all reports and data tables before statistical clearance and organisational sign off were sought. No outputs were published until all necessary approvals had been received.

Publication process

DHSC undertakes an editorial review of all GOV.UK content before publication. This is to ensure that it meets GOV.UK publishing standards, including meeting accessibility requirements.