title: Is reporting rate a good predictor of risks associated with drugs?
abstract: OBJECTIVE
  Uncertainty as to relative under-reporting plagues the comparisons of spontaneous reporting rates as a tool for decision-making in pharmacovigilance. However, it is generally accepted that under-reporting should be reasonably similar for similar drugs sharing the same indication, country and period of marketing. To test this, we compared the adverse drug reaction reporting rates to the French regional pharmacovigilance centres for six pairs of identical drug marketed at the same time by different companies under different brand names (co-marketing).
  
  
  METHODS
  All reaction reports were related to sales, to compute reporting rate; within each pair, the reporting rate ratio and its confidence interval were calculated.
  
  
  RESULTS
  The rate ratios were all between 0.76 and 1.33. Two of them were significantly different from 1 (1.28; 95% C.I. [1.01; 1.60] and 1.33; 95% C.I. [1.06; 1.74]).
  
  
  CONCLUSIONS
  These small differences in reporting rates would not warrant regulatory action and support the usual assumption of similar reporting for similar drugs.
authors.affiliation: Département de Pharmacologie, Université Victor Segalen, Hôpital Pellegrin, Bordeaux, France.
authors.forename: C
authors.initials: C
authors.lastname: Pierfitte
authors.forename: B
authors.initials: B
authors.lastname: Bégaud
authors.forename: R
authors.initials: R
authors.lastname: Lagnaoui
authors.forename: N D
authors.initials: ND
authors.lastname: Moore
mesh_terms: D016907:Adverse Drug Reaction Reporting Systems / Q000706:statistics & numerical data* / Q000639:trends; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000009:adverse effects; D064420:Drug-Related Side Effects and Adverse Reactions; D004791:Enzyme Inhibitors / Q000009:adverse effects; D005544:Forecasting; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000009:adverse effects; D011358:Product Surveillance, Postmarketing / Q000706:statistics & numerical data; D006180:Proton-Translocating ATPases / Q000037:antagonists & inhibitors; D012306:Risk
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D004791:Enzyme Inhibitors; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D006180:Proton-Translocating ATPases