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Organ type and waiting time

The waiting list is a computer system that stores medical information for every person waiting for an organ transplant in the U.S. and Puerto Rico. When a deceased donor organ becomes available, information about that organ is entered into the computer system. The system then generates a match run, which is a list of candidates who might be a good match for that organ.

To determine a potential match, the system looks at factors like:

  • Blood type
  • Tissue type
  • Medical urgency
  • Body size
  • Distance from donor hospital to recipient hospital

Blood type and other medical factors weigh into the allocation of every donated organ, but each organ type has its own individual distribution policy reflects reflect factors that are unique to each organ type:

Blue circle with white outline drawing of a kidney


  • Waiting time
  • Donor/recipient immune system compatibility (CPRA score)
  • Prior living donor
  • Distance from donor hospital
  • Survival benefit
  • Pediatric status
Purple circle with white outline drawing of lungs


  • Medical urgency
  • Likelihood of survival within 5 years post transplant
  • Immune system matching (CPRA)
  • Height match
  • Blood type
  • Pediatric status
  • Prior living donor
  • Travel efficiency
  • Proximity efficiency
Teal circle with white outline drawing of a liver


Red circle with white outline drawing of a heart


  • Medical urgency
  • Distance from donor hospital
  • Pediatric status

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