The NCES reconsidered: summary of a 1989 workshop. National Childhood Encephalopathy Study

A 1989 workshop provided a forum for independent review of the National Childhood Encephalopathy Study (NCES). No official summary will be published. Workshop panelists noted: firstly, that the magnitude of the reported association between acute neurological illness and pertussis vaccine might have been overestimated because of bias, but bias was believed unlikely to account for all of the excess risk; and secondly that because of problems with study design and methodology, the NCES is not informative with regard to long-term outcome of acute neurological illness associated with recent diphtheria-tetanus-pertussis (DTP) vaccination. The workshop panel discouraged use of the NCES estimate of the attributable risk of persistent neurological damage.