Social Determinants of Health, the Diagnostic Odyssey, and Genetic Testing for Global Developmental Delay/Intellectual Disability: A Qualitative Study.

Background: Genetic testing is recommended for all children with global developmental delay or intellectual disability (GDD/ID) without a clearly-identifiable acquired etiology, as it leads to a rare disease diagnosis up to 40% of the time and has implications for medical management and family planning. However, families often experience years-long journeys from the time of initial presentation with developmental concerns to the time of genetic testing, if it is completed at all. An implementation science-based approach to understanding determinants of genetic testing for GDD/ID is ideal for identifying key targets for future strategies to improve uptake. Methods: The Health Equity Implementation Framework was used to adapt a semi-structured qualitative interview guide from a previous study. Interviews were conducted with 18 caregivers of children with GDD/ID who had been evaluated in pediatric neurology clinics at a single tertiary care institution. Over half of participants (55.6%) self-identified with at least one historically underrepresented demographic (33.3% Black/African American, 27.8% with high school or less education, 27.8% with high neighborhood-level area deprivation, 11.1% rural). Content analysis was performed using inductive and deductive coding. Content saturation was reached. Results: Six themes reflected multilevel factors influencing uptake of genetic testing: (1) caregiver search for answers, advocacy, and empowerment; (2) real-world healthcare accessibility; (3) financial strain and insurance coverage; (4) trust and communication with providers; (5) racial disparities and discrimination; and (6) social support and community networks. Most caregivers viewed genetic testing positively. Pathways to testing were often complex and uneven. Social determinants (insurance, employment flexibility, rurality, family structure, and racism) shaped families' ability to access timely testing and follow-up. System-level barriers such as uncoordinated referrals, inconsistent provider knowledge, and long wait times compounded these challenges. Together, these factors created unequal diagnostic journeys for families, even within the same health system. Conclusions: We identified caregiver-informed targets to improve the quality and equity of care for patients with GDD/ID including insurance coverage, diagnostic efficiency, resource availability and awareness, healthcare navigation, and cultural humility. These targets inform the development and adaptation of implementation strategies to improve uptake and reduce the protracted time of the diagnosis and genetic testing journey. Trial registration: Not applicable.