First-Accept Match is a term for the scheme that is currently used for KPD. The idea is simple: match a new donor/recipient pair to the first compatible donor/recipient pair that can be found.
The most straight-forward way to match KPD pairs. Whenever a new pair comes into the system, find the first one that matches and perform the transplant. See below for why this scheme is not the best choice.
|First-Accept Match finds only one match|
|Optimized Match looks at all possibilities and finds the most matches possible|
With First-Accept Match, Pair 1 matches the center pair because it's the first one that matches. Pair 2 does not get matched, even though a solution exists that matches both 1 and 2.
The solution is to use a better algorithm for matching compatible pairs. In fact, Optimized Match is guaranteed to give us the most and best matches possible for any criteria we choose.