title: Understanding erectile dysfunction medication preference studies.
abstract: OBJECTIVE
  The existence of three phosphodiesterase 5 inhibitors has resulted in an increase in the marketing of the drugs. This has led to a shift in focus from scientifically rigorous endpoints such as efficacy and adverse event profiles to patient preference.
  
  
  RESULTS
  Although no consensus currently exists as to the correct methodology for preference studies, some basic guidelines should be adhered to, including: (1) the double-blinding of drug administration; (2) non-biased drug administration instructions; (3) an adequately conducted crossover study; (4) comparison of equivalent doses; (5) standardized preference assessment; (6) declaration of patient demographics; and (7) rigorous statistical analysis. These factors are discussed in the light of the three published preference studies.
  
  
  CONCLUSIONS
  In the final analysis, it is unclear to this author how preference studies impact upon clinician decision-making when confronted by a patient with erectile dysfunction.
authors.affiliation: Department of Urology, Weill Medical College of Cornell University, New York Presbyterian Hospital, 525 East 68th Street, New York, NY 10021, USA. jpm2005@med.cornell.edu
authors.forename: John P
authors.initials: JP
authors.lastname: Mulhall
mesh_terms: D002986:Clinical Trials as Topic; D018592:Cross-Over Studies; D003627:Data Interpretation, Statistical; D007172:Erectile Dysfunction / Q000188:drug therapy*; D006801:Humans; D008297:Male; D010726:Phosphodiesterase Inhibitors / Q000627:therapeutic use*; D010818:Practice Patterns, Physicians'
chemical_list: D010726:Phosphodiesterase Inhibitors