Background: California's workers' compensation law experienced an historic change on January 1, 2005. Previous methods used to rate permanent disability were replaced by new methods to rate permanent impairment. We sought to estimate the difference in ratings under the old and new law.
Methods: We obtained 218 reports on injured workers from attorneys who represented injured workers. A disability expert rated disability and 15 physicians rated impairment.
Results: Average percentage point ratings for impairment under the 2005 law were approximately one third the size of ratings for disability under the old law. This estimate showed little variation across demographic groups, physician-evaluators, or injured body part.
Conclusion: Because cash benefits are keyed to impairment ratings, benefits for permanently disabled workers may decrease as much as 60% under the new law.