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Publication, Part of

Dentists' Working Patterns, Motivation and Morale - 2018/19 and 2019/20

Data Quality

Introduction

The Dentists’ Working Patterns, Motivation and Morale series of Official Statistics (formerly known as Dental Working Hours) presents findings from the biennial Dental Working Patterns Survey for self-employed primary care NHS/Health Service dentists in England, Northern Ireland, Scotland, and Wales. (Please see Annex A for a copy of the survey.)

The survey runs every two years and collects separately data for the previous and current financial year. All primary care dentists in the United Kingdom who conducted some NHS/Health Service work during one or both of the financial years covered by the survey are invited to submit a survey response although participation is voluntary.

The results relate to dentists with varying levels of self-employment earnings from NHS/Health Service although some may also have income from private dental work. However, dentists who perform only private dentistry are not invited to participate in the survey and thus are not covered by the results.

The report includes a time series of results since the surveys were first run, presenting results from 2008/09 onwards for England, Northern Ireland, and Scotland and for 2018/19 and 2019/20 for Wales.

The report content and structure are agreed by the Dental Working Group (DWG) in response to user and stakeholder needs. DWG is a technical group with a UK wide remit and membership whose primary role is to carry out agreed programmes of work to meet the requirements relating to doctors’ and dentists’ remuneration (including the associated Review Body on Doctors’ and Dentists’ Remuneration (DDRB)). The members of the DWG are shown in the ‘Relevance’ section.

The findings of the report are included in material submitted for consideration by the Review Body on Doctors’ and Dentists’ Remuneration.


Accuracy

As the Dental Working Patterns Survey results are based on a sample, the findings are weighted, to present the results for the overall population. To achieve this, the population is stratified, and appropriate weights are applied to minimise the effect of any bias in the constitution of the sample.

All dentists included in the analysis answered every (relevant) question on the survey.

Dentists were invited to participate in the survey using data provided as follows:

  • Data from NHS Business Services Authority (NHS BSA) were used to derive the population of dentists in England and Wales. Dentists were allocated to strata according to:
    • dental type (in England only)
    • gender
    • age
       
  • The Northern Ireland Health and Social Care Business Services Organisation (BSO) and NHS National Service Scotland, Information Services Division (ISD) provided data relating to the primary care dentist populations for Northern Ireland and Scotland respectively. Because of the smaller populations in these countries, dentists were allocated to the same strata as used for Wales:
    • gender
    • age

2018/19 survey results were weighted to the final dental populations effective on 31 March 2019. However, final-year data were not available for all countries at the time the report was produced and as a result, the mid-year dental workforce populations on 30 September 2019 were used to weight the 2019/20 results. The effect of using the mid-year data has been tested and found to be minimal and enables us to release the report in time for consideration by the DDRB which better meets the needs of users and other stakeholders. 

For each country grouping – England, Northern Ireland, Scotland, and Wales – one set of weighting factors are derived based on the strata, and the same set of weights are applied throughout. Further information is available in the Methodology .

As the results are weighted to the full-year self-employed dental population they are subject to sampling error and uncertainty. This is because using information from or about a sample of the population can never be as accurate as using information for the entire population. Apparent differences between groups and sub-group of dentists, or in results compared to the previous years may therefore not be statistically significant. In addition, small dental populations for some sub-groups mean that extreme values can have noticeable effects on the averages; in such cases, results may be subject to more uncertainty.

Statistical significance is used in this report to illustrate the extent to which users can be confident that differences between compared results are not due to chance.

Dental population figures cited in the report should not be regarded as the definitive dental populations, and they will not be the same as those published in NHS Dental Statistics for England or comparable country reports produced by NHS Digital. This is because some dentists are excluded from the DWP Survey results for methodological or data quality reasons (for example, the results are based only on those dentists that worked for a full year discounting any annual leave taken). More detail on the dental populations is in the Methodology.

All changes to the methodology, structure, content and presentation of results are discussed by the DWG prior to implementation. In addition, at each stage the report is further validated and quality assured by NHS Digital analysts unconnected with its production.

Representative Sample and Non-Responder Characteristics

To determine whether the composition of the survey responder population is representative of the overall dental population, we consider the numbers of dentists in each sub-group and found that the survey responder population is generally representative of the primary care dental population.

The survey response rate fluctuates but in all cases is lower than when it was first conducted. We monitor this carefully, and encourage participation, particularly for countries with small dental populations. There were sufficient responses for each dental cohort to analyse the survey data and to be able to demonstrate that the sample population is representative of the whole.  Nonetheless, in some cases, statistical disclosure control is applied when the respondent population is very small and the fact that some cohorts of dentists may be over- or under-represented in the survey responder population means that results should be treated with a degree of caution. Annex C of the Methodology describes in detail the representativeness of the survey responder population

We also tested the representativeness of survey data by considering average NHS/Health Service dental activity for those who did and did not respond to the survey. We found that survey responders were likely to do a greater proportion of NHS/Health Service work than non-respondents although it is difficult to predict what effect this may have on the reported figures. For example, some non-respondents may undertake more private activity and work a similar number of weekly hours compared to the responders showing high levels of NHS activity. Where it has been possible to account for differences in the survey respondent population, this has been done by stratifying the sample to account for the major variables of gender and age along with dental type for England. This will lessen some of the effects of the variable response rates. However, it should be borne in mind that the results presented in the report are from a sample of dentists rather than the entire population, and that a degree of uncertainty is typical when considering data based upon survey results.

Known Issues

As part of the validation process for DWP Survey data, all dentists who record more than 80 working hours per week are excluded from the analyses; this accounted for a very low percentage of the dental population, for example 0.2% in England and Wales in 2011/12. Since 2016, the online survey tool has included a validation rule which asks dentists to check their response if a figure greater than 80 weekly working hours has been entered. It is possible that a small number of dentists who may normally have entered a figure greater than 80 could have re-assessed their answer, which would not have happened in earlier surveys.

From the survey undertaken in 2020, we excluded all dentists recording fewer than five weekly hours of work. This accounted for a low percentage of dentists – 0.9% across the entire UK in 2020 – but has removed a source of outliers.

We also made a minor change in the way we collected responses to certain questions in the survey undertaken in 2020. In previous surveys, questions which ask respondents to estimate the amount of time spent on clinical activity and NHS/Health Service work used an on-screen slider to select values. Respondents using mobile devices and tablets found this slider difficult to use and advised us that this was an inaccurate means of data collection. As a result, we changed the collection tool in 2020 to capture these numerical values using data entry boxes instead of the sliding bar. There is, therefore, a possibility that this change to the tool affected the data collected. Footnotes have been included in affected sections as applicable.


Relevance

The findings from the Dental Working Patterns Survey that are published in the Dentists’ Working Patterns, Motivation and Morale series are cited as evidence presented to the Review Body on Doctors’ and Dentists’ Remuneration and underpins their annual recommendations on remuneration for dentists. Findings are also used to inform workforce planning and retention.

The Dentists’ Working Patterns, Motivation and Morale reports have been produced by NHS Digital with technical and specialist contributions from the Dental Working Group (DWG) which is chaired by NHS Digital and includes representatives from:

  • Department of Health and Social Care
  • NHS England
  • Welsh Government
  • Department of Health, Northern Ireland
  • Scottish Government
  • NHS National Services Scotland: Information Services Division
  • Secretariat for the Review Body on Doctors’ and Dentists’ Remuneration (DDRB)
  • NHS Business Services Authority (NHS BSA) Information Services
  • HMRC: Knowledge, Analysis and Intelligence Division
  • National Association of Specialist Dental Accountants and Lawyers (NASDAL)
  • British Dental Association which represents the views and interests of dentists

Coherence and Comparability

The primary source of data for this report is the biennial Dental Working Patterns Survey, and we invited all UK dentists who had performed some NHS/Health Service work during 2018/19 and/or 2019/20 to participate. In addition, workforce data provided by administrative systems within each country (as listed in Accuracy) were used to compile the population and weighting variables.

We urge caution if making comparisons between countries, as different dental contracts are in place in these countries.

The results for Northern Ireland and Scotland are comparable to previous survey results, which are discussed within the publication.

From the 2020 report, we have made some significant changes to the analysis for England and Wales. The 2020 report was the first time that full analysis has been produced separately for England and Wales rather than being presented as combined figures. This also coincided with an unavoidable methodological change in how we determine dental type for dentist in England and Wales and changes to the stratification used to weight results.

The methodological change in determining dental type resulted in large numbers of dentists formerly flagged as Associate dentists to be reclassified as Providing-Performer dentists. In Wales, with its small sample size, this had a very great impact upon figures and as a result there is a new time series for Wales that begins with the 2018/19 financial year.

As England has a much larger dental population, the effect of the change in the methodology for determining dental type in England is less noticeable and although we cannot apply that part of the methodology to previous years’ figures, we have calculated high-level historical figures using the new strata to provide some additional context to England’s figures. Nonetheless, we encourage all users to take great care if making comparisons with figures prior to 2018/19.


Timeliness and Punctuality

We have published the report as soon as possible after closing the survey and validating the data. There have been no issues in relation to punctuality in the production of this report. To enable us to do so, we have used mid-year population data for the weighting variables as end-of-year data is not yet available. We have evaluated the effect of using mid-year rather than end-of-year population data and found it to be minimal.


Accessibility

The report and Methodology are accessible via the NHS Digital website and can be downloaded as PDF documents. The results are also available in spreadsheet format. The publication is also accompanied by an interactive Power BI visualisation.


Performance Cost and Respondent Burden

The workforce population data used within the publication (as described in Accuracy) is a secondary use of the data and so adds no additional burden on the NHS or the dental industry. The workforce data is obtained from administrative systems within each country: NHS BSA Information Services, the Northern Ireland Health and Social Care BSO and NHS National services Scotland ISD.

The Dental Working Patterns Survey is a biennial online survey with invitations sent to dentists within the UK who performed some NHS/Health Service activity during the two financial years covered. The survey takes approximately fifteen minutes to complete and consists of 17 questions for each year. No other data source exists for this information.

There is an inevitable cost and burden when issuing a survey, however, using an online (biennial) collection system with straightforward questions has helped keep the costs and burden to a minimum.

The findings of the survey are also used in the Dental Earnings and Expenses Estimates series of Official Statistics which is also overseen by the DWG and used in the DDRB evidence submissions.


Confidentiality, Transparency and Security

All publications are subject to a standard NHS Digital disclosure risk assessment prior to issue. Disclosure control is implemented where judged necessary.

Data are held on secure, encrypted servers and transferred on secure file transfer systems or secure email. Data Sharing, Data Processing and Service Level Agreements exist between all parties involved in production of the report to ensure appropriate security levels are maintained.

The information contained in this publication are Official Statistics. The Code of Practice for Statistics is adhered to from collecting the data to publishing.

NHS Digital policies relating to Disclosure Control, Revisions, Statistical Governance and a range of other useful documents are available on NHS Digital’s website.


Last edited: 21 June 2021 3:45 pm