title: Validation of a Blood Stability Score as an easy-to-use blood sample quality index.
abstract: BACKGROUND
  The athlete biological passport (ABP) was implemented based on conservative requirements on sample storage and transport to ensure blood integrity. Blood remains stable over periods longer than the currently employed time limits. We investigated whether time and temperature requirements for sample storage can be used in a flexible model rather than based on fixed limits.
  
  
  METHODS
  A literature review was performed analyzing the stability blood variables. A Blood Stability Score (BSS) was derived to integrate the direct dependence of the degradation rate on temperature. A validation study was then carried out in real testing conditions with antidoping blood samples. Upon sample reception, a full blood count was obtained, and then again after refrigeration for an extended period.
  
  
  RESULTS
  A BSS formula integrating storage temperature (T) and collection to analysis time (CAT) was developed: BSS = CAT + 3 × T. In real testing conditions, negligible differences were observed for some variable as BSS values approached a score of 95, while no difference was observed in HGB and RET%.
  
  
  CONCLUSIONS
  This study confirms that samples can be transported for longer periods and that the adaptive time and temperature approach as formalized in a rule that the BSS should not exceed 85 guarantees the stability of RBC variables used in the ABP.
authors: Swiss Laboratory for Doping Analyses, University Center of Legal Medicine, Lausanne and Geneva, Centre Hospitalier Universitaire Vaudois and University of Lausanne, Epalinges, VD, Switzerland.
authors: N
authors: N
authors: Robinson
authors: PWC, Gilching, Germany.
authors: A
authors: A
authors: Kirchbichler
authors: Cycling Anti-Doping Foundation, Aigle, Switzerland.
authors: O
authors: O
authors: Banuls
authors: Nationale Anti-Doping Agentur Austria, Vienna, Austria.
authors: M
authors: M
authors: Mader
authors: World Anti-Doping Agency, Lausanne, Switzerland.
authors: R
authors: R
authors: Aikin
authors: World Anti-Doping Agency, Lausanne, Switzerland.
authors: P-E
authors: PE
authors: Sottas
authors: Research Center for Automated Methods in Hematology, Catholic University of Sacred Hearth, Rome, Italy.
authors: G
authors: G
authors: D'Onofrio
mesh_terms: D001800:Blood Specimen Collection / Q000379:methods*; D004300:Doping in Sports / Q000517:prevention & control; D006801:Humans; D011786:Quality Control; D012034:Refrigeration; D013048:Specimen Handling / Q000379:methods*; D013696:Temperature; D013997:Time Factors
keywords: BSS; Blood stability; biological passport; doping; red blood cell; storage; temperature