For those fact-checking centres, there are two groups of people.
One is “information professionals and social scientists”. They try to analyze the tactics and the technological advancements used by those people who spread the disinformation. Then, by understanding that, we can prevent the next wave of disinformation.
Another group of people are grassroots citizens. They share the workload from the information professionals because of the large amount of information they receive. Also, they have the social networks to spread the information back to society, so that is also very important.
By doing these things, it also gains the trust of the general public because they know they can participate in this process.