title: Evaluation of the return rate of volunteer blood donors.
abstract: BACKGROUND
  To convert first-time blood donors into regular volunteer donors is a challenge to transfusion services.
  
  
  OBJECTIVE
  This study aims to estimate the return rate of first time donors of the Ribeirão Preto Blood Center and of other blood centers in its coverage region.
  
  
  METHODS
  The histories of 115,553 volunteer donors between 1996 and 2005 were analyzed. Statistical analysis was based on a parametric long-term survival model that allows an estimation of the proportion of donors who never return for further donations.
  
  
  RESULTS
  Only 40% of individuals return within one year after the first donation and 53% return within two years. It is estimated that 30% never return to donate. Higher return rates were observed among Black donors. No significant difference was found in non-return rates regarding gender, blood type, Rh blood group and blood collection unit.
  
  
  CONCLUSIONS
  The low percentage of first-time donors who return for further blood donation reinforces the need for marketing actions and strategies aimed at increasing the return rates.
authors.affiliation: Social Medicine Department, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo - FMRP-USP, Ribeirão Preto, SP, Brazil.
authors.forename: Adriana de Fátima
authors.initials: Ade F
authors.lastname: Lourençon
authors.forename: Rodrigo Guimarães Dos Santos
authors.initials: RG
authors.lastname: Almeida
authors.forename: Oranice
authors.initials: O
authors.lastname: Ferreira
authors.forename: Edson Zangiacomi
authors.initials: EZ
authors.lastname: Martinez