Introduction
Diabetic eye disease, which comprises diabetic retinopathy and maculopathy, is one of the leading causes of sight loss among working age adults in the UK1 and throughout the world.2 From a public health perspective, a significant proportion of diabetes-related vision loss can be prevented through a systems-level approach that includes targeted education, a well-implemented community-level or national diabetic retinopathy screening (DRS) program, with timely referral pathways for further investigation, closer monitoring or treatment.3 Population-wide screening programs have been established in Iceland, Ireland and the UK, with regional and local screening programs in other parts of Europe.4 5 In the UK, DRS is managed by the National Screening Committee. In England, the National Health Service (NHS) Diabetic Eye Screening Programme (DESP) provides annual screening for approximately 3.3 million eligible people with diabetes aged 12 years and over through 57 regional DESPs. Screening clinics operate from a variety of fixed venues, for example, hospitals, community health centers and optometry practices as well as mobile screening units. Equivalent national programs in Scotland, Wales and Northern Ireland operate according to similar service specifications.
In the UK screening programs, the majority of people are screened through the ‘Routine Digital Screening’ pathway that uses digital retinal photography. Digital images of the retina are taken by ‘screeners’ and are then assessed by accredited ‘graders’. If sight-threatening retinopathy is identified, the person is either monitored more closely in a digital surveillance clinic or referred to the hospital eye service. Although uptake of screening is generally high (eg, 82.6% for England in 2018/2019), this overall figure masks variable uptake between regional programs and suboptimal attendance in particular demographic groups (eg, adults aged <35 years, mixed ethnicity groups, lower socioeconomic status groups).5–7
A recent retrospective analysis of attendance in three large urban screening programs in England serving a population of over 300 000 people with diabetes found that uptake rates were lowest among those aged 18–34 years. The odds of attending screening in this group were significantly less than the reference group of participants aged over 60, after controlling for other demographic variables (age, sex, ethnicity and socioeconomic deprivation).7 The study also analyzed new vision impairment certifications (Certificate of Vision Impairment) caused by diabetic eye disease in England and Wales from 2009 to 2019. This analysis showed that annual incidence of new certifications for vision impairment in young adults (aged <35 years) failed to show the net decline that has occurred in other age groups over the 10-year reporting period. There is good evidence that the more diabetes eye screening appointments are missed, the greater the risk that the next attendance will reveal sight-threatening disease.8
Increasing attendance to DRS among this vulnerable population group is thus a priority. A prerequisite for identifying how best to increase attendance rates is first understanding the reasons why young adults do or do not attend DRS. A recent systematic review of 69 studies reported barriers and enablers to DRS from the perspective of people with diabetes and healthcare providers.9 Barriers to DRS included, but were not limited to inaccurate diabetic registers, confusion between routine eye care and DRS, competing priorities, forgetting, fear of the procedure and screening results, diabetes denial and burnout, and financial concerns. Enablers of DRS included social support from relatives and friends, recommendations by healthcare professionals, and community-level media coverage.9 Although these findings provide a useful starting point for designing strategies to increase DRS, the review also highlighted a number of gaps in the available evidence base regarding barriers and enablers to DRS. Only two studies explored barriers and enablers from the perspective of young adults10 11 indicating that this is an under-researched population group and very few studies explored barriers and enablers to DRS from the perspective of healthcare professionals (HCPs) and systems.
Attending, providing, and encouraging DRS are all forms of human behavior.12 Therefore, exploring influences on DRS may be facilitated by the application of behavior change theories. Theories summarize the wealth of evidence in the wider literature, providing explicit statements summarizing processes that are hypothesized to regulate behavior. These can be used to explain and predict behavior, as well as identify how best to change behavior.13 The Theoretical Domains Framework (TDF)14 15 integrates constructs from 33 behavior change theories into 14 domains representing the wide range of individual, sociocultural and environmental influences on behavior (table 1). While the TDF has been used to explore influences on patient behaviors, including in the context of diabetes self-management16 17 and DRS specifically,10 18 it has been predominantly applied in implementation research to explore factors driving current clinical practice behaviors and what it would take to implement change in practice.19 To our knowledge, the TDF has not yet been applied to explore influences on attendance at DRS from the perspective of HCPs.
The primary aim of the current study was therefore to apply the TDF to conduct a national survey exploring the barriers and enablers to attendance for DRS from the perspective of a representative sample of HCPs working in the UK DESP, with a specific focus on factors influencing the provision of DRS for young adults aged 18–34 years. As part of ongoing healthcare quality improvement efforts, DRS services may have also implemented various strategies to try and improve uptake of DRS in young adults and other population groups. It is important to document what has been tried so far, in order to learn from what has worked well and also what has not. Therefore, a secondary aim of this study was to identify current strategies implemented by UK DESPs to try and increase DRS attendance in young adults.