title: What is the importance of calculating sample size?
authors.affiliation: Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brasil.
authors.forename: Cecilia Maria
authors.initials: CM
authors.lastname: Patino
authors.affiliation: Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brasil.
authors.forename: Juliana Carvalho
authors.initials: JC
authors.lastname: Ferreira
mesh_terms: D001249:Asthma / Q000517:prevention & control*; D005260:Female; D006801:Humans; D011247:Pregnancy; D016032:Randomized Controlled Trials as Topic / Q000706:statistics & numerical data; D018401:Sample Size; D013223:Statistics as Topic / Q000379:methods*; D011795:Surveys and Questionnaires