Group 0+ (leading journals) A small number of scientific journals unanimously acknowledged internationally as the best in the field. Naturally these are generalist journals with a longstanding tradition and high academic impact.
Group 0 (excellent) A small number of scientific journals offering excellence on a level close to the top journals in the field. Expert opinion is generally in agreement as to their very high quality; they are generalist journals.
Group 1 (very good) High level scientific journals of international reputation and circulation, but not among the very top journals in their field. They comprise both generalist and more specialist journals.
Group 2 (good) Scientific journals publishing articles of a generally lower quality than Group 1 journals. Generally national-circulation journals, or international journals of lesser reputation.
Group 3 (narrow) Scientific journals with a very narrow circulation or low profile.
Professional journals (P)
Group 3P Professional journals containing articles intended for professional experts in the field. Their editorial committee includes academic personalities.
Group 4P Journals containing articles essentially intended for readers working in the field.