Patient harms during delayed access to clinical genetics services. A systematic literature review and synthesis without meta-analysis (SWiM).

Delays in accessing clinical genetics services are increasing globally. This systematic review and Synthesis Without Meta-analysis investigated the types and frequency of harms during delayed access to clinical genetics services (PROSPERO CRD42024601622). We searched peer-reviewed literature across multiple databases and included Australian policies, white papers and government documents reporting patient harms. Certainty of evidence was assessed using GRADE. Five studies met inclusion criteria. The clearest signal was non-attendance, which rose with longer waits across two studies (n = 1280). Martinez et al. observed mortality among clinical genetics waiting-list patients. Oncology and other tertiary specialties with higher mortality risk are commonly referred to clinical genetics. A randomised trial (n = 590) of cancer genetics patients found psychological distress during waiting, with high baseline distress persisting despite intervention. A large cohort (n = 48,622) reported family-level harms, including deaths among at-risk relatives. Certainty was moderate for non-attendance and very low for mortality, distress and family harms due to limited studies and imprecision. Direct causal evidence and significant associations linking waiting time delays to harm remain sparse; this represents a significant gap in the evidence base. Better evidence on presentations and factors linked to harm would support more effective waiting-list management. This review characterises the types of harm experienced by patients during the clinical genetics waiting period, providing a foundation for future investigation and demonstrating opportunity for improved services. System-level action is needed, including safety evaluation of emerging models of care, structured prioritisation, improved genetics literacy and transparent waiting-list management to strengthen equity and safety.