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A landmark for popperian epidemiology: refutation of the randomised Aldactone evaluation study
  1. Elard Koch1,2,
  2. Alvaro Otarola1,2,
  3. Aida Kirschbaum1
  1. 1Division of Epidemiology, School of Public Health, Faculty of Medicine, University of Chile
  2. 2School of Health, Duoc-UC Institute, Pontifical Catholic University of Chile
  1. Correspondence to:
 Professor E Koch
 Division of Epidemiology, School of Public Health, University of Chile, 939 Independencia, Santiago, Chile;


In 1999 a great multi-site clinical trial known as the randomised Aldactone evaluation study (RALES) showed that the use of spironolactone importantly reduced complications attributable to chronic heart failure without major negative side effects. Recently, RALES has been questioned by a large scale observational study in the Ontario population. In contrast with predictions, the complications and mortality increased dramatically because of hyperkalaemia, reaching dimensions that from a public health perspective are comparable to an epidemic. This review analyses both researches in the light of Karl Popper’s science theory applying the modus tollens syllogism to the reality proposed by the main empirical enunciations that ensue from its epidemiological designs. RALES is deductively refuted because of the non-fulfillment of auxiliary assumptions that would act as reciprocal potential falsifiers in both studies, taking the logical form of a bi-conditional argument of the type: (a) P-then-Q and (b) Q-if-XP, XP being a set of potential falsifiers of Q as part of the explicit falsity content of P. From this popperian model, implications for clinical research are discussed.

  • RALES, randomised Aldactone evaluation study
  • EBM, evidence based medicine
  • CHF, chronic heart failure
  • ACE, angiotensin converting enzyme
  • RCT, randomised controlled trial
  • epidemiological methods
  • evidence based medicine
  • philosophy of science
  • popperian epidemiology
  • randomised clinical trials

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  • Funding: none.

  • Conflicts of interest: none.

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