They had an algorithm and their calculate every quartile, a lot criteria such as intensity publication etc.

The Q value of any journal is not a fix value, it is changed every year. some journals still have the same Q value, while the values of others may increase or decrease depends on the productivity of the journal (ex. no of citation per document, no of published paper, no of uncited documents,...). Moreover, some journals may exit from either scopus or ISI after it was included. As a summary, you should check the ISI or scopus list for the current year to make sure to what category the journal belongs.

Sumaia M. Al-Ghuribi , thank you so much for your clarification. All the best,

They had an algorithm and their calculate every quartile, a lot criteria such as intensity publication etc.