Time trends for injuries and illness, and their relation to performance in the National Basketball Association

Objectives: To survey injury/illness in the National Basketball Association over a 25-year period and examine the relationship of injury/illness to team performance.

Design: A retrospective correlational design.

Methods: Trends were examined in reported numbers of players injured/ill during a season and games missed due to injury/illness from seasons ending in 1986 through 2005. This period was compared to years 2006-2010, when NBA teams were allowed to increase the total number of players on the team from 12 to 15.

Results: There was a highly significant trend (p<0.0001) of increasing numbers of players injured/ill and games missed from 1986 through 2005. After the team expansion in 2006, these rates fell abruptly by 13% and 39% respectively (both p<0.0001 compared to the previous 5-year period). We also found a significant inverse association between games missed due to injury/illness and percent games won (r=-0.29, p<0.0001).

Conclusions: Results demonstrate an increased rate of injury in the National Basketball Association up until the expansion of team size in 2006. Following 2006, team expansion was positively associated with decreased injury/illness rates. The latter finding suggests the importance of maintaining a healthy roster with respect to winning outcomes.