title: 'Why me?' versus 'why now?'--differences between operational hypotheses in case-control versus case-crossover studies.
authors.affiliation: School of Health Information Science, University of Victoria, Victoria, British Columbia, Canada. malcolmmaclure@shaw.ca
authors.forename: Malcolm
authors.initials: M
authors.lastname: Maclure
mesh_terms: D000063:Accidents, Traffic / Q000706:statistics & numerical data; D001334:Automobile Driving; D001569:Benzodiazepines / Q000009:adverse effects; D015982:Bias; D016022:Case-Control Studies; D015986:Confounding Factors, Epidemiologic; D018592:Cross-Over Studies; D016208:Databases, Factual; D015340:Epidemiologic Research Design; D006801:Humans; D017891:Pharmacoepidemiology / Q000379:methods*; D012306:Risk
chemical_list: D001569:Benzodiazepines