title: The dangers of inferring treatment effects from observational data: a case study in HIV infection.
abstract: Several recent articles have implicitly questioned the need for randomized controlled trials, based on a comparison of treatment effects from observational studies and related randomized controlled trials. We present here a counterexample of a comparison of two antiretroviral drugs used in the treatment of HIV infection, in which the observational analysis gave a potentially misleading result. Examples such as this emphasize the need to regard randomized controlled trials as the primary mechanism for assessing therapeutic efficacy.
authors.affiliation: MRC Clinical Trials Unit, 222 Euston Road, London NW1 2DA, UK. d.dunn@ctu.mrc.ac.uk
authors.forename: David
authors.initials: D
authors.lastname: Dunn
authors.forename: Abdel
authors.initials: A
authors.lastname: Babiker
authors.forename: Malcolm
authors.initials: M
authors.lastname: Hooker
authors.forename: Janet
authors.initials: J
authors.lastname: Darbyshire
mesh_terms: D000328:Adult; D019380:Anti-HIV Agents / Q000494:pharmacology*; D003627:Data Interpretation, Statistical; D016049:Didanosine / Q000494:pharmacology; D004359:Drug Therapy, Combination; D015658:HIV Infections / Q000188:drug therapy*; D006801:Humans; D019370:Observation; D016032:Randomized Controlled Trials as Topic / Q000706:statistics & numerical data*; D015983:Selection Bias; D016047:Zalcitabine / Q000494:pharmacology; D015215:Zidovudine / Q000494:pharmacology
chemical_list: D019380:Anti-HIV Agents; D015215:Zidovudine; D016047:Zalcitabine; D016049:Didanosine