Neonatal screening

Abstract
# Performance is hard to monitor {#article-title-2} EDITOR,—We agree with Allison Streetly and colleagues that any additions to the established neonatal screening programme for phenylketonuria and congenital hypothyroidism should be assessed for effectiveness, including impact on the performance of the overall programme.1 But we would go further and suggest that such an assessment would prove difficult because of inherent problems with the existing neonatal screening programme, which need to be addressed first. Streetly and colleagues assume that 99% of babies are tested for phenylketonuria and congenital hypothyroidism, though the figure may be lower, at least in London, where coverage with …