title: What time-lag for a retraction search on PubMed?
abstract: BACKGROUND
  To investigate fraud and errors, scientists have studied cohorts of retraction notices. These researches have been performed using a PubMed search on publication type "retraction of publication" which retrieves the notices of the retractions. We assessed the stability of the indexation of retraction notices over a 15-month period and what was the time-lag to get stability.
  
  
  RESULTS
  A search on notices of retraction issued in 2008 was repeated every 3 months during 15 months from February 2011. The first search resulted in 237 notices of retraction. Throughout the study period, 14 discrepancies with the initial search were observed (6%). We found that the number of retraction notices became stable 35 months after the retraction.
  
  
  CONCLUSIONS
  The time-lag observed in this study has to be taken into account when performing a PubMed search.
authors: Hospices Civils de Lyon, Pôle Information Médicale Evaluation Recherche, Unité de Recherche Clinique, Lyon F-69003, France. evelyne.decullier@chu-lyon.fr.
authors: Evelyne
authors: E
authors: Decullier
authors: Laure
authors: L
authors: Huot
authors: Hervé
authors: H
authors: Maisonneuve
mesh_terms: D006801:Humans; D016247:Information Storage and Retrieval; D039781:PubMed / Q000706:statistics & numerical data*; D012180:Retraction of Publication as Topic; D013997:Time Factors