A Scientifically Credible Approach to Impairment Ratings

Friday, September 10, 2010 | 0

By Robert J. Barth, Ph.D. and Christopher Brigham, M.D.

Impairment ratings are an important issue for claims professionals. In state workers’ compensation systems they drive more than $20 billion of costs. In addition, they are routinely used in other arenas, including federal cases (FECA and Longshore and Harbor Workers Act), automobile casualty, and personal injury claims.

The Sixth Edition of the American Medical Association Guides to the Evaluation of Permanent Impairment, published in 2007, is the new international standard serving as the first step in medically assessing disability. The Sixth Edition introduced a paradigm shift in assessing impairment. An innovative methodology is used to enhance the relevancy of impairment ratings, improve internal consistency, promote greater precision, and simplify the rating process. The approach is based on a modification of the conceptual framework of the International Classification of Functioning, Disability, and Health (ICF). Standardized methodology is applied to each chapter to enhance the relevancy of impairment ratings, improve internal consistency, and promote ease of application to the rating process.

An analytical framework based on the ICF generates five impairment classes that permit the rating of the patient from no impairment to most severe. A diagnosis-based grid has been developed for each organ system that arranges commonly used ICD-9 diagnoses within the five classes according to the consensus-based dominant criterion. Functionally based histories, physical findings and broadly accepted objective clinical test results are integrated where applicable to help physicians determine the grade within the impairment class.

Dr. Christopher Brigham is the senior contributing editor for the Sixth Edition of the AMA Guides. He has personally conducted a wealth of scientific research on the use, misuse, and abuse of impairment rating systems. His research findings have clearly demonstrated that physicians typically misuse or even ignore the Guides, thereby causing the overwhelming majority of impairment ratings to be inaccurate. Typically, an impairment rating provided by a local physician in an individual case will be two to three times higher than the Guides would have called for. Dr. Brigham’s detailed analysis of this phenomenon has helped to identify key issues regarding what is going wrong with such erroneous ratings, and has resulted in the development of new best practice strategies. Such strategies call for strict adherence to the most current professional standards, both in regard to obtaining ratings that are accurate and unbiased and in regard to recognizing and managing erroneous ratings.

<b>Florida’s Approach Is Problematic</b>

The scientifically established tendency for doctors to misuse (or even ignore) professional standards regarding impairment ratings is compounded by Florida’s idiosyncratic approach. Specifically, the Florida workers' compensation system uses the 1996 Florida Uniform Permanent Impairment Rating Schedule (FUPIRS). The FUPIRS was based in part on the Fourth Edition of the AMA Guides, which was published in 1993. Therefore, the FUPIRS is 14 to 17 years out of date.

The antiquated nature of the FUPIRS is a clear cause for concern. As with other areas of medicine, concepts and approaches for impairment evaluation improve with time. For example, some treatments are found to be ineffective and are dropped from practice and new approaches are adopted. This also occurs with the medical assessment of impairment. With the change in impairment methodology, there will also be changes in impairment values associated with specific conditions. As clinical medicine evolves and there is increased efficacy of treatment, it is hoped that improved outcomes will reduce impairment previously associated with injury and illness.

There have been criticisms directed toward prior editions of the Guides, and the FUPIRS is vulnerable to such criticisms because of its antiquated nature. In addition to the high error rate that was discussed above, such criticisms include the failure to provide a comprehensive, valid, reliable, unbiased, and evidence-based rating system.

The AMA has responded to such criticisms by revising the Guides, but the antiquated nature of the FUPIRS has prevented Florida from benefiting from such revisions. For example, the state is failing to benefit from the AMA’s development of impairment ratings for conditions that may result in functional loss, but which were not previously eligible for a rating. Similarly, unreliable assessment procedures, such as range of motion for the spine, have been eliminated.

Additionally, the newest edition of the AMA Guides endorses the fundamental principle that medical treatment is designed to improve function and decrease impairment. In contrast, the FUPIRS involves an inherent assumption that some forms of treatment, such as spine surgery, carry an intention of doing harm to patients, in that the FUPIRS specifies that such surgery actually increases impairment.

<i>Christopher Brigham M.D. is the senior contributing editor for AMA Guides to the Evaluation of Permanent Impairment Sixth Edition, editor-in-chief of the AMA’s Guides Newsletter, editor of the AMA’s Guides Casebook, and chairman of Impairment Resources, LLC .

Robert J. Barth, Ph.D., is owner of of Barth Neuroscience in Chatanooga, Tenn.</i>