AMA Guides Impairment Ratings Erroneously Elevated – Best Practices Approach is Expert Review of All Impairment Ratings

The AMA Guides to the Evaluation of Permanent Impairment, Fifth Edition, are the standard for defining the impact of an injury or illness. Unfortunately the vast majority of ratings are incorrect, typically overrated and the errors are often undetected. This observation was confirmed in our 2005 study and reconfirmed in our current study. The conclusion is that all impairment evaluation reports should be reviewed by an expert on the Guides – this intervention is very cost-effective.

California Study

Of 658 California impairment critiques performed between July 2006 and February 2007, 571 (87%) were incorrect, with the average original rating 18.7% whole person permanent impairment (WPI) and the average revised (corrected) rating 4.9% WPI. Review of 73 consecutive cases from one client revealed an error rate of 82% among the ratings performed, with the average original rating of 12.3% WPI and the revised (corrected) rating of 3.7% WPI. The marked difference in ratings between the old PDRS were predicted in our May 17, 2005 Workers Compensation Insurance Rating Bureau study

National Study

Of 874 national impairment critiques performed between July 2006 and February 2007, 751 (86%) were incorrect, with the average original rating 18.5% whole person permanent impairment (WPI) and the average revised (corrected) rating 5.2% WPI. In the automobile casualty arena every impairment rating was incorrect.