Question regarding League Leaders, etc.

[Leftos]

What makes a player eligible for inclusion in the League Leaders table? Do they have to have played a certain percentage of games (like at least half, at least 10) or something? As for scoring stats, is the criteria the same, or do they have to have a certain amount of attempts as well?

Same goes for the Metric Stats table as well I guess; the League Leaders version of it doesn't include all the players of each team. For example, a player with a PER of 30 but with just 3 out of 30 games played will be in the Team's Metric Stats table, but not in the League's Metric Stats table. What do you think the exact or approximate criteria is for that?

EDIT: Found it:
http://www.nba.com/leader_requirements.html