title: A low tension between individual and societal time aspects in health improved outcomes.
abstract: OBJECTIVE
  To review intertemporal choices, involving decisions with a trade-off between something now and something later. These choices are common in health both at an individual and societal level.
  
  
  METHODS
  The present value of an outcome, for example, the amount of money or the health outcomes in various aspects, is equivalent to the value of a future outcome discounted with the delay of time. The concept of diminishing value over time is positive discounting. Economic forecasts generally use discount rates in which the value of a future dollar is less than the value of a present dollar, and where the discount rates are similar for the individual investor and society. The value of future health is commonly thought of as similar to the value of future money. Yet, the individual may rationally choose a discount rate that is exceedingly low or even negative. This paradox is particularly relevant when considering primary and secondary prevention, where initial and continuing costs may precede beneficent outcomes by decades, making discount rate selections the dominant factor in determining decisions.
  
  
  CONCLUSIONS
  We suggest that the societal perspective should also recognize that discount rates for health outcomes are largely irrelevant and that even negative discount rates have crucial relevance.
authors.affiliation: Stanford University School of Medicine, Department of Medicine, Division of Immunology and Rheumatology, 1000 Welch Road, Suite 203, Palo Alto, CA 94304, USA. monicaortendahl@hotmail.com
authors.forename: Monica
authors.initials: M
authors.lastname: Ortendahl
authors.forename: James F
authors.initials: JF
authors.lastname: Fries
mesh_terms: D003657:Decision Making; D015438:Health Behavior; D006304:Health Status; D006801:Humans; D012919:Social Behavior; D013995:Time