title: Time to publication as full reports of abstracts of randomized controlled trials in cystic fibrosis.
abstract: OBJECTIVE
  To determine 1) what proportion of abstracts of randomized controlled trials (RCTs) presented at international conferences on cystic fibrosis (CF) are published as full reports, 2) time to publication, and 3) factors that might delay or prevent publication.
  
  
  METHODS
  At the end of 1995, the Cochrane CF Group's register of RCTs contained 199 abstracts describing 180 RCTs. Abstracts were identified by handsearching 44 abstract books of three international CF conferences over a 30-year period. We searched the register for subsequent full reports of these RCTs and used survival analysis to investigate time to publication. Using the log-rank test, we examined 1) whether there is a difference in time to publication between reports where the investigators concluded that the test treatment was as effective as or better than the control treatment, and reports where it was not, and 2) whether there is a difference in time to publication according to sample size.
  
  
  RESULTS
  Thirty-two percent of the 178 abstracts analyzed were subsequently published in full. Survival analysis indicated that the proportions published before 12 months, 2 years, and 5 years were 8.1%, 29%, and 40% respectively. No difference in time to publication was identified when the abstracts were stratified according to conclusions or sample size; no significant association (P > 0.05) existed between time to publication and both sample size and conclusions together.
  
  
  CONCLUSIONS
  Only a small proportion of abstracts of RCTs presented at international conferences on CF are followed by full publication, and usually only after several years. Therefore, many potentially valuable studies do not reach a wide audience. However, we found no consistent factors which might delay or prevent publication.
authors.affiliation: Respiratory Unit, Alder Hey Children's Hospital, Liverpool, UK.
authors.forename: K
authors.initials: K
authors.lastname: Cheng
authors.forename: C
authors.initials: C
authors.lastname: Preston
authors.forename: D
authors.initials: D
authors.lastname: Ashby
authors.forename: U
authors.initials: U
authors.lastname: O'Hea
authors.forename: R L
authors.initials: RL
authors.lastname: Smyth
mesh_terms: D000043:Abstracting and Indexing / Q000706:statistics & numerical data*; D001877:Books; D016001:Confidence Intervals; D003226:Congresses as Topic / Q000706:statistics & numerical data; D003550:Cystic Fibrosis; D004311:Double-Blind Method; D006801:Humans; D011642:Publications / Q000706:statistics & numerical data*; D016032:Randomized Controlled Trials as Topic / Q000706:statistics & numerical data*; D012042:Registries; D012044:Regression Analysis; D015203:Reproducibility of Results; D012693:Serial Publications / Q000706:statistics & numerical data; D016019:Survival Analysis; D013997:Time Factors; D006113:United Kingdom