Implementation Timeframes for the Addition of New Conditions to Newborn Bloodspot Screening Programmes: A Scoping Review.

Severe combined immunodeficiency (SCID) and spinal muscular atrophy (SMA) are being added to the Newborn Bloodspot Screening (NBS) programme in the Republic of Ireland. To support this expansion, we conducted a scoping review to identify reported timeframes for implementing national, regional or state-wide expanded NBS programmes. We performed a scoping review of the literature published between 2015 and 2025. Eligible articles described the timeframes for implementation of expanded NBS programmes for SCID, SMA or additional metabolic conditions. Sources included PubMed, Embase, citation searching, the International Journal of Neonatal Screening and grey literature. A narrative synthesis was undertaken. Fourteen articles met the inclusion criteria, describing the addition of new conditions-SCID (N = 7), SMA (N = 4), or multiple conditions (N = 3) to expanded NBS programmes in the United States (US), Europe (Belgium, Catalonia, the Czech Republic, Estonia, Germany, Norway, Poland, Portugal, Slovakia, Slovenia, Sweden, and Tuscany), Hong Kong and New Zealand. In most jurisdictions, the implementation of NBS programmes for new conditions took two to six years. The implementation of NBS for new conditions requires considerable time and coordinated efforts. Further research providing greater detail on the specific implementation steps, along with associated timelines, would provide valuable guidance for jurisdictions aiming to expand NBS programmes globally.