During the 2004/2005 season, the Central Board of FIBA decided to use the smaller and lighter basketball for female basketball players. The previous ball was a "size 7" and FIBA moved to "size 6" - a difference of only 34 mm in circumference. A smaller ball for women was suggested for the first time in 1935, as it was thought that a smaller ball would increase women's shooting accuracy. Women players in the United States had been playing with the smaller ball for some time - and generally had a positive reaction to it - but FIBA held off until the 21st century.
A study was released by Naja Podmenik, Bojan Leskosek and Frane Erculj to test the hypothesis that a smaller ball would increase player accuracy. (And the study can be found right here.)
The study looked at 12 teams from the European Championships from 2001, 2003, 2005 and 2007.
When using a smaller ("size 6") basketball:
* There is no significant difference in field goal percentage between using the small ball and the standard size ball.
* Guards and forwards will take more frequent 3-point shots because the lighter ball boosts player confidence.
* Free throw percentage goes *down* with the use of the lighter ball. The study could not determine why this was the case.
* Dribbling, passing, and handling the smaller ball were not tested in the study.
So this paper answers one question - the smaller ball might make players more confident but it doesn't increase accuracy. The questions about ball handling remain - and I'm looking forward to a future study about free throw accuracy by some researcher 50 years from now.