title: Instrumental variable analyses for observational comparative effectiveness research: the paired availability design.
authors.forename: Laura Faden
authors.initials: LF
authors.lastname: Garabedian
authors.forename: Alan M
authors.initials: AM
authors.lastname: Zaslavsky
authors.forename: Stephen B
authors.initials: SB
authors.lastname: Soumerai
mesh_terms: D057186:Comparative Effectiveness Research / Q000379:methods*; D015986:Confounding Factors, Epidemiologic; D006801:Humans; D064887:Observational Studies as Topic / Q000379:methods*