title: Demographic characteristics and prevalence of serologic markers among blood donors who use confidential unit exclusion (CUE) in São Paulo, Brazil: implications for modification of CUE policies in Brazil.
abstract: BACKGROUND
  This study evaluated demographic profiles and prevalence of serologic markers among donors who used confidential unit exclusion (CUE) to assess the effectiveness of CUE and guide public policies regarding the use of CUE for enhancing safety versus jeopardizing the blood supply by dropping CUE.
  
  
  METHODS
  We conducted a cross-sectional analysis of whole blood donations at a large public blood center in São Paulo from July 2007 through June 2009, compared demographic data, and confirmed serologic results among donors who used and who have never used CUE (CUE never).
  
  
  RESULTS
  There were 265,550 whole blood units collected from 181,418 donors from July 2007 through June 2009. A total of 9658 (3.6%) units were discarded, 2973 (1.1%) because CUE was used at the current donation (CUE now) and 6685 (2.5%) because CUE was used in the past (CUE past). The CUE rate was highest among donors with less than 8 years of education (odds ratio [OR], 2.78; 95% confidence interval [CI], 2.51-3.08). CUE now donations were associated with higher positive infectious disease marker rates than CUE never donations (OR, 1.41; CI, 1.13-1.77), whereas CUE past donations were not (OR, 1.04; CI, 0.75-1.45).
  
  
  CONCLUSIONS
  The CUE process results in a high rate of unit discard. CUE use on an individual donation appears predictive of a high-risk marker-positive donation and, thus, appears to contribute modestly to blood safety. The policy of discarding units from donors who have previously CUE-positive donations does not improve safety and should be discontinued.
authors.affiliation: Fundação Pró-Sangue, Blood Center of São Paulo, São Paulo, SP, Brazil. cesarnt@uol.com.br
authors.forename: Cesar
authors.initials: C
authors.lastname: de Almeida-Neto
authors.forename: Jing
authors.initials: J
authors.lastname: Liu
authors.forename: David J
authors.initials: DJ
authors.lastname: Wright
authors.forename: Alfredo
authors.initials: A
authors.lastname: Mendrone-Junior
authors.forename: Pedro L
authors.initials: PL
authors.lastname: Takecian
authors.forename: Yu
authors.initials: Y
authors.lastname: Sun
authors.forename: Joao Eduardo
authors.initials: JE
authors.lastname: Ferreira
authors.forename: Dalton
authors.initials: D
authors.lastname: de Alencar Fischer Chamone
authors.forename: Michael P
authors.initials: MP
authors.lastname: Busch
authors.forename: Ester Cerdeira
authors.initials: EC
authors.lastname: Sabino
mesh_terms: D000293:Adolescent; D000328:Adult; D001782:Blood Donors / Q000706:statistics & numerical data*; D001938:Brazil; D003430:Cross-Sectional Studies; D046148:Donor Selection / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012959:Socioeconomic Factors; D012984:Software; D014584:User-Computer Interface; D055815:Young Adult