cRF Calculator
cRF: 0%
Mp: 0
Fm: 0
Ad: 0
Blood
HLA-B/DR
A
B
BW
CW
DR
DQ
DPB
cRF Calculator

Calculator results display:

result display image

Matchability point bands:

BG 1 2 3 4 5 6 7 8 9 10
A 360 279 228 178 146 115 87 63 19 0
B 70 54 42 35 29 24 19 14 6 0
O 405 311 247 193 157 128 103 74 34 0
AB 23 14 10 8 6 3 2 0

For each blood group, patients are assigned to an Mp band based on the maximum number of favourably matched donors (Fm) they have. The Mp bands are defined by specific Fm threshold values as outlined in the table above.

NB: The banding is subject to change as the calculator is updated by NHSBT-ODT. There is no set schedule.

HLA type for matchability calculation:

Matchability estimates how many levels 1 and 2 mismatched, ABO-identical, and HLA-compatible donors (a.k.a. favourably matched donors, Fm) are available for a patient within the 10,000 donor cohort.

The calculation is based on broad HLA specificities. For determining favourable matches (levels 1 and 2), only HLA-B and DRB1 are needed: HLA-A does not affect this categorisation.

HLA mismatch levels for HLA-A, B and DR
Level Summary Combinations included
1 000 000
2 [0 DR and 0/1 B] or [1 DR and 0 B] 100, 010, 110, 200, 210, 001, 101, 201
3 [0 DR and 2 B] or [1 DR and 1 B] 020, 120, 220, 011, 111, 211
4 [1 DR and 2 B] or [2 DR] 021, 121, 221, 002, 102, 202, 012, 112, 212, 022, 122, 222
Ref: NHSBT-ODT Kidney Allocation Policy - POL186
How to use the calculator

i. Clear data Click the icon or the cRF Calculator name to clear all data and start afresh.

ii. Select blood group Blood group A is selected by default. Click on the blood group name to select a different blood group.

iii. Select antibody specificities Click on the antigen name to select or deselect the antigen. The selected antigen(s) will be highlighted in blue. Click on the locus name to toggle between selecting all or none of the specificities of that locus.

iv. Matchability calculation HLA-B and DRB1 types are required for matchability calculation. Select the HLA-B and DRB1 specificities from the drop down lists. For homozgous types, select the same specificity for both alleles or select one and leave the other unselected.

v. Donor cohort selection Only 3,642 donors in the 10,000 cohort are DP typed. Click the A to toggle between all donors and only those with DP types D.

vi. Selected specs Selected antibody specificities can be copied to the clipboard by clicking the icon. This copies the specificities text without any formatting and spacing. Double click each specificity to remove it and uncheck the corresponding checkbox.

vii. Input specs Input antigen specificities by typing in the text box. Antigens can be separated by spaces or commas. The input is not case sensitive. CWn and DPBn specificities can be input as Cn or DPn. Press enter after typing to process the input.

Data source: hla-mm-and-crf_2024.xlsb
File size signature: 24,099,579.
Created by: Mian Chen - March 2024.
API documentation: matchbox API
GitHub repo: machnine/matchbox
GitHub pkg: ghcr.io/machnine/matchbox:latest
Match Level Summary Combinations Donors
Levels 1 and 2
(favourable)		 0 DR and 0/1 B 000, 100, 010, 110, 200, 210
1 DR and 0 B 001, 101, 201
Level 3 0 DR and 2 B 020, 120, 220
1 DR and 1 B 011, 111, 211
Level 4 1 DR and 2 B 021, 121, 221
2 DR 002, 102, 202, 012, 112, 212, 022, 122, 222
Total (n/10,000):