title: Design and statistical analysis of observational studies.
authors: I M
authors: IM
authors: Usta
authors: J
authors: J
authors: Awwad
authors: A H
authors: AH
authors: Nassar
mesh_terms: D005215:Fasting / Q000009:adverse effects*; D005260:Female; D006801:Humans; D007752:Obstetric Labor, Premature / Q000209:etiology*; D011247:Pregnancy