TY  - JOUR
AB  - Background: Retention of study participants in observational studies is essential to maintaining the representativeness of the population, minimizing selection bias, and assuring sufficient statistical power. The aim of this report is to describe the structures and strategies used to retain participants in The Environmental Determinants of Diabetes in the Young (TEDDY) Study, an observational study of children at increased genetic risk for type 1 diabetes followed in an intensive protocol from birth until age 15. Methods: Teague et al.’s systematic review of study retention strategies identified four domains: barrier reduction; community building; follow-up/reminder; and tracing strategies (1). TEDDY retention strategies were categorized into each of these domains. A fifth category presented strategies unique to TEDDY. Results: TEDDY employed over one hundred retention strategies during the 15 years of follow-up; many could be categorized within the Teague domains. Strategies unique to TEDDY included (1) study structures to support retention; (2) risk communication and education strategies specific to this population; (3) Data-informed retention strategies that addressed protocol challenges in real-time; and (4) implementation of a re-engagement protocol for those who had withdrawn from the study. Conclusion: Pediatric cohort studies should include strategies, structures, and resources to address retention at the study's initiation and on an ongoing basis. Retention strategies should not remain static but change with the developmental needs of the child. Collecting and analyzing data on an ongoing basis permits retention strategies to be put in place to address protocol and retention challenges in real time. Trial registration: ClinicalTrials.gov Identifier: NCT00279318.
AU  - Gesualdo, P.*
AU  - Melin, J.*
AU  - Karban, R.*
AU  - Crouch, C.*
AU  - Killian, M.*
AU  - Hopkins, D.*
AU  - Adamsson, A.*
AU  - Stock, J.
AU  - Johnson, S.B.*
AU  - Baxter, J.*
AU  - Germany clinical center (Ziegler, A.-G.
AU  - Sanverdi, C.
AU  - Heublein, A.
AU  - Hummel, S.
AU  - Grätz, W.
AU  - Knopff, A.
AU  - Köger, M.
AU  - Koletzko, S.
AU  - Ramminger, C.
AU  - Roth, R.
AU  - Schmidt, J.
AU  - Scholz, M.
AU  - Warncke, K.
AU  - Winkler, C.
AU  - Müller, L.)
C1  - 73395
C2  - 57044
CY  - 525 B Street, Ste 1900, San Diego, Ca 92101-4495 Usa
TI  - Structures and strategies for retaining an international pediatric cohort from birth: Lessons from The Environmental Determinants of Diabetes in the Young (TEDDY) study.
JO  - Contemp. Clin. Trails Comm.
VL  - 44
PB  - Elsevier Inc
PY  - 2025
SN  - 2451-8654
ER  - 

TY  - JOUR
AB  - Viral infections in the first year of life are associated with islet autoimmunity and type 1 diabetes risk. The Anti-Viral Action against Type 1 Diabetes Autoimmunity (AVAnT1A)- study is a clinical phase IV investigator initiated, randomised, controlled, multicentre, primary prevention trial conducted to determine whether vaccination against COVID-19 from 6 months of age reduces the cumulative incidence of islet autoantibodies or type 1 diabetes in children with elevated genetic risk. Additionally, it investigates the role of viral infections in the etiology of islet autoimmunity by intense surveillance within the first two years of life. Infants aged 3.00–4.00 months from Germany, Belgium, UK and Sweden are eligible if they have a >10 % expected risk to develop islet autoantibodies by age 6 years as determined by HLA DR/DQ genotype, polygenic risk score and family history of type 1 diabetes. A total of 2252 eligible children are randomized 1:1 to COVID-19 vaccine (Comirnaty® 3 μg Omicron XBB.1.5 or future new variants) or placebo (0.9 % Sodium Chloride) administered three times. Children are followed until the minimum age of 2.5 years and maximum age of 6 years. The intervention is accompanied by analyses of immune and metabolic parameters to determine changes induced by viral infections and to investigate mechanisms by which viral infection may lead to islet autoimmunity. The Sponsor is the Klinikum rechts der Isar, Technical University Munich. The study was approved by Clinical Trials Information System (CTIS, EU Trial number: 2023-507348-35-00) and by Integrated Research Application System (IRAS, IRAS-ID: 1009668).
AU  - Hummel, S.
AU  - Käßl, A.
AU  - Arnolds, S.
AU  - Achenbach, P.
AU  - Berner, R.*
AU  - Casteels, K.*
AU  - Hyöty, H.*
AU  - Kordonouri, O.*
AU  - Larsson, H.E.*
AU  - Lundgren, M.*
AU  - Marcovecchio, M.L.*
AU  - Owen, C.*
AU  - Pfirrmann, M.*
AU  - Robson, S.C.*
AU  - Szadkowska, A.*
AU  - Szypowska, A.*
AU  - Tree, T.*
AU  - Weiss, A.
AU  - Ziegler, A.-G.
AU  - Bonifacio, E.
C1  - 73221
C2  - 56965
CY  - 525 B Street, Ste 1900, San Diego, Ca 92101-4495 Usa
TI  - Anti-viral action against type 1 diabetes autoimmunity: The GPPAD-AVAnT1A study protocol.
JO  - Contemp. Clin. Trails Comm.
VL  - 44
PB  - Elsevier Inc
PY  - 2025
SN  - 2451-8654
ER  - 

TY  - JOUR
AB  - Background: Although detection of children at high risk of developing type 1 diabetes and diagnosis of early stages is possible, up to now there exists no approved therapy to delay or prevent type 1 diabetes. Thus it is vital to develop evidence-based interventions. For this a sufficient number of trial participants is crucial but difficult to obtain especially in asymptomatic children. Aim: Identifying family characteristics that lead to or impede trial participation and analyze reasons stated by families for non-participation. Methods: Participants for the Fr1da Insulin Intervention study are recruited from the Fr1da study, a population based screening for early stage type 1 diabetes in Bavaria. Families with eligible children were invited to enroll. We analyzed sex and age of the child, distance of the family to the study center in Munich and the existence of a first degree family member with type 1 as possible influential factors for study participation. We also analyzed reasons stated by families who declined study participation in a phone interview. Results: Of 146 eligible children 77 (53%) were enrolled into the trial. None of the tested family characteristics differed significantly between the enrolling and the families not participating, but in general enrolling families lived closer to the study site than families not participating. This is also reflected in the reasons given by non-participating families. The most frequent reason stated were time restrictions. The second most frequent reason was the venous blood draw. Conclusion: The factors for non-participation identified in this project need be taken into account for the design of future trials in young children to ensure proper recruitment and thus to generate valid results for medical treatment of children. More research on the reason of participation and non-participation in clinical trials is needed.
AU  - Kick, K.*
AU  - Assfalg, R.
AU  - Aydin, S.*
AU  - Bechtold-Dalla Pozza, S.*
AU  - Böcker, D.*
AU  - Braig, S.*
AU  - Bunk, M.*
AU  - Dunstheimer, D.*
AU  - Durmashkina, A.*
AU  - Ermer, U.*
AU  - Gavazzeni, A.*
AU  - Gerstl, E.M.*
AU  - Heinrich, M.*
AU  - Herbst, M.
AU  - Kriesen, Y.*
AU  - Kuhnle-Krahl, U.*
AU  - Müller, H.*
AU  - Nellen-Hellmuth, N.*
AU  - Ockert, C.*
AU  - Ramminger, C.*
AU  - Sindichakis, M.*
AU  - Tretter, S.*
AU  - Warncke, K.*
AU  - Achenbach, P.
AU  - Ziegler, A.-G.
AU  - Hoffmann, V.
C1  - 54208
C2  - 45295
SP  - 170-173
TI  - Recruiting young pre-symptomatic children for a clinical trial in type 1 diabetes: Insights from the Fr1da insulin intervention study.
JO  - Contemp. Clin. Trails Comm.
VL  - 11
PY  - 2018
SN  - 2451-8654
ER  -