The Dental Working Patterns (DWP) survey was first run in January 2008 and considered the working patterns of dentists in England and Wales for 2006/07 and 2007/08. Since then the survey has been extended to include dentists in Scotland and Northern Ireland and has been undertaken every two years. Differences between the 2018/19 and 2019/20 survey and previous iterations are summarised below.
2006/07 and 2007/08
In the NHS Business and Provider and Performer Arrangement section, the 2006/07 and 2007/08 survey did not specifically ask for data related to primary care dentistry, whereas subsequent surveys do. It is, therefore, possible that the 2006/07 and 2007/08 report contained some secondary care dentistry in the results.
The 2006/07 and 2007/08 survey asked how time devoted to dentistry was split between clinical and administrative work. This question was changed for the 2008/09 and 2009/10 and subsequent surveys to ask how time was split between clinical and non-clinical work, noting that the latter may include administration and management duties. This aimed to ensure that all time spent on dentistry was included. This difference may affect the way that dentists answered the question for the two surveys. Other questions in later surveys were slightly reworded to try and make them as clear as possible[1].
2008/09 and 2009/10
Both the working and business arrangement questions following the 2008/09 and 2009/10 survey were altered. Each question had an additional option to enable further identification of those dentists who have incorporated their business: in the working arrangement question, a new option entitled ‘Associate – Incorporated’ was added and in the business arrangement question, the ‘Partnership’ option was divided into ‘Limited Liability Partnership’ and ‘’True’ Partnership’, with the former representing the incorporated option of a business held as a partnership[2].
The number of Associate dentists that indicated they were ‘Associate – Incorporated’ was low (about 6% of all dentists) and, as a result, they were left in the Associate cohort for the analysis in this and earlier reports. The main reason for their ongoing inclusion was that the analysis in years before 2010/11 and 2011/12 included Associates who had incorporated their business and their retention has allowed the time series to be unbroken.
2010/11 and 2011/12
The survey was collected online from 2012 onwards rather than by a postal return, as used in earlier surveys. There was a decrease in the overall return rate, the size and effect of which is discussed in more detail in Annex C.
2012/13 and 2013/14
The last four DWP surveys (covering 2012/13 to 2019/20) have included seven questions on motivation and one on morale. Please see Annex A in the main report for a copy of the latest survey and the additional questions. Whilst none of the other workload and arrangement questions were altered from the 2010/11 and 2011/12 survey onwards, the inclusion of the motivation and morale questions might have affected how dentists answered the other questions.
2014/15 and 2015/16
For the last three DWP surveys (covering 2014/15 to 2019/20) dentists in England were sent only an invitational email and not an accompanying letter; dentists in Wales, Scotland and Northern Ireland received both. The survey response rate in England has decreased for the two most recent surveys and is discussed in more detail in Annex C.
The motivation and morale of dentists has been decreasing since these attributes were first measured in the 2012/13 and 2013/14 DWP Survey. As a result, it was agreed at the Dental Working Group (DWG) that the 2016/17 and 2017/18 survey should have an additional question on the potential causes of low morale. More information about the development of this question is included in Annex D. This question was included at the end of the survey after all the other questions had been addressed but it is possible that its inclusion may have affected dentists’ responses.
2016/17 and 2017/18
Between the 2012/13 and 2013/14 and the 2016/17 and 2017/18 surveys, questions three and eleven, and questions four and twelve, which ask respondents to estimate the amount of time they spend on clinical activity and NHS/Health Service work respectively, used an on-screen slider for users to select values. Respondents using mobile devices found it difficult to use the slider, suggesting it was an inaccurate means of data collection. As a result, the sliders were replaced by data entry boxes in the last survey.
Summary
It is difficult to predict the effect these differences could have had on how survey questions were answered but they should be borne in mind when considering the results.