A key difference between Special Olympics competitions and those of other sports organizations is that athletes of all ability levels are encouraged to participate. Competitions are structured so that athletes compete with other athletes of similar ability in equitable divisions. An athlete's ability is the primary factor in divisioning Special Olympics competitions. The ability of an athlete or team is determined by an entry score from a prior competition or the result of a seeding round or preliminary event at the competition itself. Other factors that are significant in establishing competitive divisions are age and gender.