Study of over 6,200 impairment ratings spanning 5 years reveals 78% error rate

A study of more than 6,200 impairment ratings spanning 5 years revealed an error rate of 78 percent, resulting in ratings averaging more than twice what was appropriate. Ratings from eight states were examined, with 81 percent of the cases being from California and 91% rated using the Fifth Edition of the American Medical Association Guides to the Evaluation of Permanent Impairment. While not a random sampling - all cases had been submitted for expert review - the study sheds light on reasons for inaccuracy in impairment ratings and suggests areas for improvement. It echoes findings of a similar study performed in 2005.

The study, recently published in the AMA Guides Newsletter, was conducted by staff and associates of Impairment Resources. Among key observations:

• There are significant problems with interrater reliability with Fifth Edition ratings.
• Most ratings were performed incorrectly, resulting in ratings averaging more than twice what was appropriate.
• Problems are more common in jurisdictions where physicians use approaches other than those specified by the AMA Guides than in jurisdictions where physicians are trained, experienced, and perform in accordance with best practices.
• Inaccurate ratings are often the result of bias, confusion, and misapplication of the Guides.
• Preliminary data suggest that both the error rate and magnitude of error may be less with Sixth Edition ratings.

Currently, 16 states use the Fifth Edition; 10 use the Sixth Edition; 10 use earlier editions; 7 use state-specific guidelines; and no guidelines are specified in the remaining states.

Study authors suggest stakeholders take steps to drive more accuracy in impairment ratings.

• Ensure that impairment ratings are performed by knowledgeable, skilled, and unbiased examiners with training in use of the Guides, and that ratings are independently reviewed by personnel who are skilled and knowledgeable.
• Clients requesting reviews should take a hands-on approach to reviewing physician credentials, defining standards, and supplying all relevant records.
• All stakeholders should advocate for adoption of the most accurate and advanced standards, the Sixth Edition.