6741 Screening children for type 1 diabetes in the UK (The ELSA Study): an assessment of return rates and withdrawals

Objectives The EarLy Surveillance for Autoimmune Diabetes study (ELSA, www.elsadiabetes.nhs.uk) is exploring the feasibility and acceptability of screening children for pre- symptomatic type 1 diabetes (T1D). One route of participation is through a home testing kit which collects a dried blood spot (DBS) on a card for measurement of islet- specific autoantibodies (AAb). Any child screening positive for AAb is invited for venous confirmation and staging through glucose challenge testing. Educat ion, follow-up and intervention trials are offered to children at-risk. The objective of this poster is to evaluate DBS card return rates, reasons for non-return and reasons for withdrawal in the first 12 months of the study. Methods DBS kit return rates were analysed and reasons for non-return or withdrawal explored through telephone interviews with families. Results Of 10,375 children consented to the ELSA study since November 2022, 8565 (83%) registered for home-testing. 5952 (57%) of these home-testing kits have been returned. Of those kits returned, over 98% were returned within 3 months of being posted out. There was a withdrawal rate of 0.6% (n=58). Of the 60 families who withdrew, reasons given for withdrawal included that the child declined (n=27), parents requested to withdraw (n=11), the test was too invasive (n=3), the child was diagnosed with diabetes before DBS testing (n=3), the family were too busy (n=2), concern with the study (n=2), lost kit (n=1) and that the family were unable to obtain the DBS sample (n=1). Attempts were made to contact 67 families that had not returned the DBS kit but had not withdrawn from the study. 32 were eventually contacted by phone and reasons for non-return gently explored. In 41% (n=13) of the families contacted, the DBS testing was too 'scary' for the child, 28% (n=9) misplaced the kit and requested another, 9% (n=3) were still planning to do the test, 9% (n=3) forgot, 9% (n=3) said they wanted to withdraw without giving a specific reason, and 3% (n=1) were diagnosed with type 1 diabetes before they could do the DBS. Conclusion Screening for T1D reduces rates of presentation in diabetic ketoacidosis, improves metabolic control and facilitates access to immunoprevention trials. Data from the ELSA screening trial shows that DBS home testing return rates are comparable to other home screening programmes.1–3 The predominant reason for withdrawal was that the child declined testing and the predominant reasons for non-return of kits were that the child found DBS testing 'scary' or loss of the kit. References Ylitalo K, Camp B, Meyer R, et al. Barrier and facilitators or colorectal cancer screening in a federally qualified health center. Journal of the American Board of Family Medicine 2019;32(2): 180–190. Fisher M, Wayal S, Smith H, et al. Home sampling for sexually transmitted infection and HIV in men who have sex with men: A prospective observational study. PLoS One 2015;10(4): e012810. Smith J, Vaz O, Gabert C, et al. Recruitment strategies and HPV self-collection return rates for under-screened women for cervical cancer prevention. PLoS ONE 2023;18(d): e0280638.