title: On the controversy about the efficacy of the antimeningococcal B vaccine: methodological pitfalls.
abstract: The present communication analyses methodological problems related to evaluating the protection given by the anti-meningococcal B vaccine to children under four years of age in a case-control study carried out in Sao Paulo, Brazil. Detection of a hospital selection bias, among other disturbing features of the study, suggests that the efficacy of the vaccine was underestimated. Altogether, data presented support a wider use of the Cuban-produced vaccine to reduce morbidity and mortality from serogroup B meningococcal disease.
authors.affiliation: Departamento de Epidemiologia e Métodos Quantitativos em Saúde, Escola Nacional de Saúde Pública, Rio de Janeiro, RJ, 21041210, Brasil.
authors.forename: E A
authors.initials: EA
authors.lastname: Costa