Evaluation of Newborn Screening Programme Implementation for Inborn Errors of Metabolism in Lagos State

Newborn screening (NBS) for inborn errors of metabolism (IEM) offers the opportunity for presymptomatic diagnosis and timely intervention, preventing irreversible intellectual and physical disability. Lagos State has piloted an NBS programme, yet systematic evaluation of its implementation fidelity, coverage, and follow-up outcomes remains sparse. This study evaluated the implementation status of the Lagos State NBS programme for selected IEMs including phenylketonuria, congenital hypothyroidism, and galactosaemia. A mixed-methods programme evaluation enrolled 300 mother-neonate pairs at five implementing hospitals and reviewed 24 months of NBS programme records. Implementation metrics assessed included sample collection rate within 48 hours of birth, laboratory turnaround time, positive predictive value, and follow-up cascade completion. Qualitative data from healthcare providers identified supervision gaps and parental refusal as notable challenges. Turnaround time exceeded the programme target of five working days in a significant proportion of samples, largely due to logistics. Recall and follow-up of screen-positive neonates was suboptimal. Recommendations include establishing dedicated NBS coordinators at each facility and strengthening the logistics of dried blood spot transport to the state reference laboratory. Keywords: newborn screening, inborn errors of metabolism, programme evaluation, Lagos State, follow-up cascade