Visits consisted of 4 appointments per year until 4 years of age, followed by 2 per year until 15 years of age, and included interviews, food records, questionnaires, and blood and other samples. Blood samples tested for 3 islet autoantibodies: insulin, insulinoma-associated protein 2, and glutamic acid decarboxylase.
Eligible participants were still enrolled and active at child-age 48 months and excluded children who developed T1D-related autoantibodies before the age of 4. The analysis included 4600 families with children aged 3.5 months to 48 months, of which 60.5% (n = 2784) completed all 11 visits.
According to univariate analysis, the sex of the child and whether the mother was working outside of the home, was a single parent, or believed the child’s risk could be reduced were unrelated to missed visits.
The multivariate model revealed study visit compliance was the highest in first born children (P >.001), those whose mothers were older (P >.001), those who resided in Sweden (P >.001), and for those whose mothers were more satisfied with the initial 1-year TEDDY study (P >.001). Sixty-five percent of mothers with the highest study satisfaction (scores of 5 or 6) completed all study visits compared with 48% of least satisfied mothers (scores of 0 – 2). Paternal participation was also linked to better compliance (P >.001). Although the father’s study satisfaction also predicted study visit compliance (P = .029), it was not deemed statistically significant in models including maternal satisfaction.
Predictors of substandard compliance included mothers who smoke (P >.001), experienced post-partum depression (P = .034), and reported anxiety about their child’s risk of developing diabetes (P = .002). Ethnic-minority children were also more likely to have poor visit compliance (P = .049).
Investigators noted the study was limited by including only children up to 4 years of age. Additionally, findings may be less applicable to studies with less demanding research protocols.
“This information can contribute to future strategies designed to improve study visit compliance in longitudinal pediatric studies,” investigators concluded.
References:
- Melin J, Lynch KF, Lundgren M, Aronsson CA, Larsson HE, Johnson SB. Factors assessed in the first year of a longitudinal study predict subsequent study visit compliance: the TEDDY study. Eur J Med Res. 2023;28(1):592. Published 2023 Dec 15. doi:10.1186/s40001-023-01563-z
- Besser REJ, Bell KJ, Couper JJ, Ziegler AG, Wherrett DK, Knip M, et al. ISPAD clinical practice consensus guidelines 2022: stages of type 1 diabetes in children and adolescents. Pediatr Diabetes. 2022. https://doi.org/10.1111/pedi.13410.
This article was initially published by our sister publication, HCP Live.