The Registry Atlas · How we check
How we check where you can join
The Registry Atlas says whether, and how, people who live in each country and territory can join a stem cell donor registry. Here’s where those answers come from, what our labels mean and how to tell us when something’s wrong.
Last updated
How we check a way to join
We start with each registry’s own pages: who can join, how, what it costs and what happens next.
Where a rule depends on something else, such as a health card, we read the government’s own page too. For the risks of donating, we use published studies of unrelated donors. For which stem cell treatments are approved, we use a government health service or the medicines regulator.
We read each page’s own text, not a summary of it, and note the date we read it.
We call a way to join verified only when the registry’s own current page offers it to people who live in that place.
Every fact on our pages lists its source, with the source’s own date and the date we last read it.
We read the joining page and the rules again on a schedule, and again in the two days before a guide is published or changed.
We check that each join button still opens the registry’s own page. Those checks are never counted as visits from readers, and we never sign up to test a link.
A page that doesn’t open is never treated as closed: it is read again before any page changes.
When no registry signs people up
“No registry to join” means that, after the searches below, no registry was found that signs up people who live in that place. The place’s page says what is there instead.
- Before we say it, we look: in the World Marrow Donor Association’s directory of registries, and on official sites such as the health ministry’s, the national blood service’s and those of registries nearby that might sign up people who live there.
- We search in the place’s own official languages where we can, not only in English.
- We record each search with where we looked, the language and the date, and the place’s page lists what each search found.
- Where sources disagree, the page shows what each one says, and it shows no join button until they agree.
- We look again on a schedule, and we want to hear from you if you know of a way to join.
What if there’s no donor registry where you live?Tell us about a registry
What “Checked” means
Our pages show up to three dates.
- Checked
- The date at the top of a page is the date of the oldest fact it depends on. If one rule was last read a month ago and the rest last week, the page shows the earlier date.
- Link checked
- The last date we confirmed that a join button opens the registry’s own page.
- Next check due
- The latest date we’ll read the page’s sources again.
What our labels mean
Every place carries one of five labels, unless no one lives there year-round. A label says what we could check about joining a registry from that place. It says nothing about how much donors are needed there.
- You can join here67 of 250 places
A registry signs up people who live in this place, and we’ve read its own current rules.
- Join through a service that covers this place16 of 250 places
No registry is based here, but one based somewhere else signs up people who live here, and its own rules say so.
- Joining is limited, paused or just starting8 of 250 places
A registry exists, but joining is open only in some ways or places, has paused, or is still being set up.
- No registry to join152 of 250 places
No registry signs up people who live in this place. The place’s page says what is there instead.
- Sources differ0 of 250 places
Sources disagree about how people who live here can join. The place’s page shows what each one says.
- No one lives here year-round7 of 250 places
No one lives in this place year-round, so there’s no registry to join from it.
Words we use
Plain words, used the same way on every page.
- Place250 in all
- A country or territory. We list every one in the international standard list of country codes (ISO 3166-1), and Kosovo, including the places where no one lives year-round.
- Registry
- A stem cell donor registry keeps a list of volunteers willing to give blood stem cells to a patient they don’t know, and searches it when a patient needs a donor.
- Way to join
- A form, a swab kit or a donor drive that a registry offers to people who live in a place.
- A service that covers this place
- A registry based somewhere else that signs up people who live in this place, and says so on its own pages.
- Records
- Each adult donor a registry lists for searching is a record. We say records, not people, because the figures count entries on registries’ lists.
- Cord blood units
- Blood from a newborn’s umbilical cord, donated after the birth and stored so it can be searched for a patient. We never add cord blood units to adult donor records: they’re counted apart.
- World figures
The Registry Atlas quotes WMDA’s live Search & Match statistics, with the date we read them.
WMDA’s yearly Global Trends Report counts differently, from what 103 registries and cord blood banks in 61 countries reported at the end of 2025, some of which don’t list in Search & Match: about 46.8 million adult donor records and, separately, about 906,000 cord blood units.
Sources: WMDA, Search & Match statistics; WMDA, Global Trends Report 2025. Checked .
Change log
What’s changed
Changes to the Registry Atlas as a whole, the newest at the head of the list. When something that matters changes on one page, such as an age limit, who can join or a join link, that page says what changed and when.
We added a page for places where no registry signs people up: what people who live there, people from there living abroad and patients’ families can do.
What if there’s no donor registry where you live?Our registry finder became the Registry Atlas: every country and territory is listed, and each place we’ve researched has its own page, including the places where no registry signs people up.
See every placeWe published the Australia guide, with pages for Christmas Island, the Cocos (Keeling) Islands and Norfolk Island.
Why we started with Australia
Australia was ready. People who live there join one national registry, Stem Cell Donors Australia, and its rules for joining could be read and checked on its own pages.
We had also gathered more evidence about joining there than anywhere else, so we chose to start with Australia.
That order says nothing about need. It isn’t a ranking, and no guide means its patients need donors more than anyone else’s.
Checked before it was published
Sources
The world figures on this page come from these sources. The rest of the page describes how we work. The sources behind each place are listed on its own page.
Statistics
- World Marrow Donor Association (WMDA). Total Number of Donors and Cord blood units (Search & Match statistics) (opens in a new tab).Checked
- World Marrow Donor Association (WMDA). Global Trends Report 2025, summary slides (opens in a new tab). Published .Checked
Data version hub-2026.10.24-3+2e57f0bf
Something wrong or out of date?
Tell us, and we’ll check it
Use our contact form, with the page’s title and what looks wrong. The form doesn’t accept web addresses, so the title is enough.
Know of a way to join that we’ve missed? Tell us the place and the registry’s name, and we’ll look.
We check it against the registry’s own pages. When we change something that matters, such as an age limit, who can join or a join link, the page says what changed and when.