Effect of a tailored leaflet to promote diabetic retinopathy screening among young adults with type 2 diabetes: a randomised controlled trial

Background: Young adults with type 2 diabetes (aged 18–39 years) are at risk of early onset and rapid progression
of diabetic retinopathy, the leading cause of blindness and vision loss in working age adults. Early detection via
retinal screening can prevent most vision loss, yet screening rates are consistently lower among this priority
population than the general diabetes population. We aimed to test the effect of a tailored, evidence-based brief
health behaviour change intervention (leaflet) on self-reported screening uptake, and previously identified social
cognitive determinants of retinal screening.
Methods: A pragmatic, two-arm randomised controlled trial was conducted from September 2014 to April 2015.
Participants were stratified by prior screening uptake (Yes/No) and randomly allocated to intervention (leaflet) or
‘usual care’ control (no leaflet). Primary outcome was self-reported screening uptake four weeks post-intervention
for ‘No’ participants who had not previously screened for diabetic retinopathy. Secondary outcome variables were
changes in knowledge, attitudes, normative beliefs, intention and behavioural skills for all participants, irrespective
of prior screening behaviour. To assess intervention effects on secondary outcome variables, we conducted
independent samples t-tests (two-tailed) on pre-post change scores.
Results: 129 young adults (26% no prior retinal screen) completed baseline; 101 completed post-intervention.
Power to determine effect on the primary outcome was curtailed by low recruitment of individuals with no prior
retinal screen and loss to follow-up. Attrition was associated significantly with country of birth, language spoken at
home, and marital status. Significant intervention effect was observed for one secondary outcome variable:
knowledge of diabetic retinopathy (p = .03) with moderate effect (partial eta squared η2 = .05); no adverse effects
were reported. Control group participants received the leaflet at study completion.
Conclusions: This study confirms that a well-designed eye health and retinal screening promotion leaflet can increase
knowledge of diabetic retinopathy, an important screening predictor. The study highlights the challenges of conducting
‘real-world’ health behaviour change research with this priority population, providing insights for clinicians and researchers.
Strategies to recruit, engage and retain hard-to-reach populations are discussed including nonconventional alternatives to
randomised controlled trial designs. Trial registration: ACTRN12614001110673, UTN No.: U1111–1161-9803. Registered 20
October 2014 - retrospectively registered https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=367127.