eMedicine - Impairment Rating of Neuromusculoskeletal Conditions : Article by Oregon K Hunter, Jr

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Impairment Rating of Neuromusculoskeletal Conditions

Article Last Updated: Oct 24, 2006

AUTHOR AND EDITOR INFORMATION

Section 1 of 11

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Authors and Editors
Introduction To Impairment And Disability Evaluation
Concepts In Disability Evaluation
Impairment Rating Guides
Impairment Rating Examples
Example Of Disability Evaluation
Legal And Other Issues Of Impairment Rating And Disability Evaluation
Psychiatric Issues Of Impairment Rating And Disability Evaluation
Sample Deposition Questions On Impairment Rating And Disability Evaluation
Multimedia
References

INTRODUCTION TO IMPAIRMENT AND DISABILITY EVALUATION

Section 2 of 11

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Authors and Editors
Introduction To Impairment And Disability Evaluation
Concepts In Disability Evaluation
Impairment Rating Guides
Impairment Rating Examples
Example Of Disability Evaluation
Legal And Other Issues Of Impairment Rating And Disability Evaluation
Psychiatric Issues Of Impairment Rating And Disability Evaluation
Sample Deposition Questions On Impairment Rating And Disability Evaluation
Multimedia
References

Impairment rating of neuromuscular conditions in the United States originated in the 1950s. The American Medical Association (AMA) released the first edition of its AMA Guides to the Evaluation of Permanent Impairment in 1971. The fifth edition is currently available.

The impairment rating is an estimate of the severity of human impairment based on acceptable medical standards. Various reference books, including the AMA Guides, provide a standard method of analysis to evaluate, report on, and communicate information about impairments to any human organ system.

According to the AMA Guides, impairment is an alteration of an individual's health status that has been assessed by medical means. Impairment is used to describe a static or stable condition that has had sufficient time to allow optimal tissue repair and that is unlikely to change, despite further medical or surgical therapy. The Florida Impairment Schedule defines impairment as anatomic or functional abnormality or loss after maximal medical improvement (MMI) has been achieved.

The purpose of impairment rating is to represent impairment by using a generally accepted system to estimate the degree to which illness or injury diminishes an individual's capacity to daily activities. Activities of daily living (ADL) include self-care, personal hygiene, preparing and eating food, communication (both spoken and written), maintaining posture, standing, sitting, caring for home and personal finances, walking, traveling, recreational and social activities, and work-related activities. An individual with an impairment may or may not have sufficient capacity to meet the demands of a particular profession or occupation.

First, the examiner should gather information to document the nature of the impairment and its consequences. Review the patient's medical history, as well as his or her office and hospital records. Use multiple sources of information to promote objectivity and eliminate bias. For purposes of evaluation, the patient's medical condition should be stable and unlikely to change in the future despite further treatment. Treatment at this point is palliative rather than restorative.

Obtain clinical information from the patient's medical records and from physical examination. Compare clinical information from several sources to check for consistency. Resolve disparities, when possible, if the clinical information is inconsistent. Use medically accepted and scientifically derived data based on the patient's normal functioning whenever data are available. The impairment rating values in the guides estimate the extent of impairments based on the authors' clinical experience, judgment, and consensus. Impairment ratings are estimates of the degree of impairment, based on the physician's judgment, experience, training, skill, and thoroughness.

Other factors in determining the rating of impairment include a consideration of the sensitivity, specificity, accuracy, reproducibility, and interpretation of findings from laboratory and clinical procedures, as well as a recognition of interobserver variability in interpretation.

In the impairment-rating process, a number derived from well-structured and thorough observations is assigned. The strength of medical support for an impairment estimate depends on the completeness and reliability of the patient's medical documentation. The rating does not convey any information about the effect of the impairment on the person's capacity to meet personal, social, or occupational demands.

The fourth edition of the AMA Guides suggests, "If, in spite of an observation or test result, the medical evidence appears not to be of sufficient weight to verify that an impairment of a certain magnitude exists, the physician should modify the impairment estimate accordingly, describing the modification and explaining the reason."

Many practitioners confuse the terms impairment and disability. Disability refers to an individual's inability to complete a task or a duty. Disability is an alteration of the individual's capacity to meet personal, social, or occupational demands or statutory or regulatory requirements because of an impairment. Disability arises from a discrepancy between the limitations an impairment places on an individual and the external tasks that must be performed (eg, tasks in an occupational setting).

Impairment, however, is an artificial construct—usually one the legal system creates—to attempt to quantify the person's diminution in health. Specifically, "An impairment is a deviation from normal in a body part or organ system and its functioning," according to the fourth edition of the AMA Guides. However, normal is a vague term that varies greatly depending on many factors, such as age and sex. Normal is not a fine point or an absolute reference in terms of physical and mental functioning or good health. Most often, normality is a range or a zone, as it is with vision and hearing.

Many state disability systems adopt an impairment guide or schedule for calculating damages. For example, Florida has adopted the Florida Uniform Permanent Impairment Rating Schedule (FUPIRS). This schedule is loosely modeled after the AMA Guides and purports to give impairment ratings based on various injuries or illnesses.

As a practical example, an individual may have minor impairment and still be considered totally disabled. For example, an uneducated bricklayer may have 5% impairment due to lumbar strain. His physical restrictions may make it impossible for him to continue working in his field. If he does not have the education to be retrained, he is effectively unable to return to work. Therefore, the extent of his impairment may be only 5%, but he is l00% disabled in terms of employment. In another example, a noted author and lecturer may have sustained a catastrophic injury causing thoracolumbar paraplegia. His impairment rating may be 70% according to the AMA Guides. However, because he can continue his work with little to no interruption, he may be considered to have no vocational disability.

In summary, the impairment rating alone, without a consideration of the extent of disability and loss of function, does not provide a complete picture of the effect of illness or injury on a particular individual.

CONCEPTS IN DISABILITY EVALUATION

Section 3 of 11

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Authors and Editors
Introduction To Impairment And Disability Evaluation
Concepts In Disability Evaluation
Impairment Rating Guides
Impairment Rating Examples
Example Of Disability Evaluation
Legal And Other Issues Of Impairment Rating And Disability Evaluation
Psychiatric Issues Of Impairment Rating And Disability Evaluation
Sample Deposition Questions On Impairment Rating And Disability Evaluation
Multimedia
References

Evaluating disability is more complex and involved than the impairment rating discussed in the previous section. By definition, disability involves a consideration of many factors beyond the purview of impairment rating. Although impairment addresses a loss or deficit in any psychological, physiologic, or anatomic structure or function, disability encompasses vocational, educational, psychosocial, and financial factors, to name only a few, in addition to the rated impairment.

Whereas the impairment-rating system incorporates a coefficient of impairment, assessment of disability has no such rating system, but disability benefits are awarded by means of an administrative process the Social Security Administration (SSA) developed as a result of the Social Security Act Amendments of 1954. These amendments established the Disability Determination Units from which claimants referred to clinical examiners for an assessment of impairment in regard to appeals regarding Social Security Disability Income (SSDI) that the SSA adjudicates.

Assessment systems

The most established disability-assessment system is the one the SSA developed for persons who claim a degree of impairment that makes the resulting disability significant. That is, impairment is significant enough that these individuals report being completely incapable of engaging in gainful employment, and, thus, they are unable to support themselves independent of state or federal subsidy.

The SSA expanded the traditional definition of impairment in determining an individual's fitness for work by adding consideration of factors that define function as a part of the disability assessment. For example, individuals who allege that they cannot work because of angina pectoris may find that the condition itself is not enough to permanently disqualify them from work. In evaluating the individual's ability to function in a clinically controlled work setting with typical physical and mental simulations, other issues directly related to diagnosis may apply. Examples are the character, location, and duration of pain and how it evolves, what relieves it, and how quickly relief is achieved. These factors, in addition to the patient's diagnosis, may be enough for the clinical examiner to recommend that the patient not return to gainful activity.

The SSA disability-evaluation process is bureaucratic, lacking a skilled and well-trained medical examiner. An analysis reviews of all medical records with input from a medical review officer but without any interaction with or examination of the claimant. Therefore, as Pace states, the records must be sufficiently complete to enable any independent reviewer who does not examine the claimant to determine the nature, limiting effects, and duration of impairment on the basis of only the written reports. The quality of the review is contingent on the cooperation of the medical community to provide records to the SSA, a shortcoming of the current review process.

The Social Security Disability Evaluation System (SSDES) heavily relies on the establishment and definition of the respective diagnosis and on the principle that diagnosis can be determined objectively by using diagnostic and laboratory studies. Function is a secondary consideration, or, in terms of the 1994 AMA impairment-rating protocols, its application is that of a differentiator in determining the degree of impairment or the residual functional capacity of the claimant outside impairment parameters. In essence, function merits little consideration in impairment rating. Other systems predating the SSA evaluation process similarly focused on impairment, with some acknowledgment given to the effect of function on impairment.

The earliest system, the McBride system (1936), was based on Workers' Compensation law and readily adopted by Workers' Compensation Boards in various states. The fundamental principle was that functional and/or social deficiencies were as relevant as impairment itself. Therefore, McBride implemented an average rating test that included the component of disabling functional deficiencies in addition to the component of disabling physical impairments, as follows (Mooney, 1987):

Earl McBride, MD, first expressed the problem of standardization in evaluating impairment, stating, "[G]uessing at percentages seems to be more in order than scientific reasoning. Consequently, the industrial commissioners in weighing and applying the evidence often make a practice of splitting the difference in percentages instead of weighing the facts scientifically. This is a reflection on the integrity of the medical profession more than it is on the commission."

It was not until 1956, around the time of the Social Security Act Amendments, that the AMA studied the issue of standardization in impairment rating. The AMA Board of Trustees appointed an ad hoc committee of physicians to develop standards for rating disability and impairment and to compile guides that all physicians could follow. From the deliberations of this committee evolved a structured framework and method of analysis "...through which physicians [could] evaluate, report on, and communicate information about the impairments of any human organ system."

What the AMA had hoped to establish was a standardized system for physicians, one that could produce consistent ratings, perhaps with models for standard calculations for impairments rated by 2 or more independent physicians at different times. However, in the 44 years since the AMA committee met, the goal of establishing a universally accepted method seemed untenable, though evaluation standards have been established. The medical community remains divided on whether to use the guides and accompanying evaluation protocols, and questions have been raised about reliability and validity associated with the AMA standards and protocols. The establishment of consistent evaluation standards that impairment-rating clinicians use has not been attained yet.

The American Academy of Orthopaedic Surgeons published the Manual for Orthopedic Surgeons in Evaluating Permanent Physical Impairment in 1962. This manual was based on the AMA protocols (eg, range of motion [ROM], amputation) but deviated somewhat, as it included a pain scale in line with documented organic pathology. The manual further included impairment ratings for orthopedic conditions and procedures not included in the AMA Guides. For example, in this rating system, fractures of the tibial plateau are considered a possible source of impairment, the extent of pain associated with this diagnosis is rated as well.

H. Kessler, MD, published Disability: Determination and Evaluation in 1970, which was somewhat based on the McBride model. However, he focused on loss of function in his disability decision. Although Kessler supported McBride's efforts to delineate the physical and functional components of disability, he maintained that units of measure could be assigned to these components to provide a rational rating coefficient. Although this approach is valid for assessing the upper extremities (UEs) and lower extremities (LEs), rating the 3 spinal regions remains difficult. Kessler rationalized that emotion was the dominant factor in the persistence and intensity of back pain and noted that, in most patients reporting this problem, pain was the only complaint. He concluded that the impetus of rating spinal impairment was to use criteria based on the successful performance of ADLs.

Current challenges

The focus of this article thus far has been a review of the common and peer-reviewed disability rating systems that the medical community and the judicial system currently accepts and uses. The systems reviewed emphasize the documentation of impairment, with disability as a secondary consideration in the examiner's clinical judgment of whether a person is disabled or not. This emphasis remains true today despite the mandate of the Americans with Disabilities Act of 1990 to integrate job simulation and assessment of the claimant's ability to function into medical-examination protocols for return-to-work after disability leave.

The question remains: Why has the medical community avoided an evaluation of true work function based on biomechanical and ergonomic simulation, preferring the traditional independent medical examination (IME) method of systems review, reflex studies, strength measures, and records review?

The answer to that question may be found in a review of the literature regarding attitudes, training, and misuse of terminology that has perplexed the medical and judicial system for years. In 1983, Ziporyn interviewed Talmadge Hiebert, MD, founder of the National Association of Disability Evaluating Professionals (NADEP). Hiebert took issue with terms used in the rating forms of workers'-compensation and the SSDI programs, on which the disability and impairment were used interchangeably. He remarked that the examining physician is confused when asked about disability versus impairment issues. Hiebert further commented that physicians do not receive any formal training in their medical-school programs regarding evaluating or measuring function and that peer-reviewed articles about measuring functional capacity usually do not appear in the medical journals and instead appear in physiology, ergonomics, and exercise journals.

In 1988, Luck and Florence acknowledged that the problem rests primarily with a lack of standardization among medical specialties. They specifically noted that many physicians use more than 1 system for disability evaluation or impairment rating. Like Hiebert, they found that many physicians are uncertain about the difference between impairment and disability when drawing conclusions from their ratings.

One interesting observation was that impairment rating is often viewed as an onerous and frustrating task because it lacks the positive reinforcement of helping the sick patient and strains the physician-patient relationship. In other words, physicians prefer the role of a healer and medical practitioner to that of an examiner of impairment and/or disability, which often leads to an adversarial relationship between themselves and their patients.

In 1993, Abel-Moty et al identified the problem primarily as a skill deficiency among physicians who have great difficulty in translating the results of medical impairment evaluations into functional measures. Physicians have not had adequate training in functional measurement and disability evaluations to allow them to translate impairment into functional disability.

Demand for impairment rating and functional-capacity evaluation

Despite the problems discussed above, impairment-rating services and functional-capacity evaluations (FCEs, ie, disability examinations) are in high demand from the legal and insurance professions because of rising healthcare costs and subsequent lawsuits. The demand is specifically high in the areas of personal injury (eg, auto liability), work-related injury (ie, workers' compensation), and product liability. More than 15 years ago, Ziporyn stated, "[E]ach year American physicians receive hundreds of thousands of requests to determine impairment and disability, and every physician at some point in his or her career will be called upon to do so."

Occupational statistics further support the need for such services, expanding the scope of the medical-service delivery system at a rapid pace. Before the 1989 healthcare census, musculoskeletal injuries and cumulative trauma disorders were the second largest group of occupational illnesses in the United States. The most common and expensive complaint of workers with musculoskeletal injuries is low-back injuries that cost an estimated $14 billion dollars annually.

The insurance and legal communities have recognized the need for disability and impairment-rating services, given that the number of working days lost per injury increased by 150% and that workers'-compensation costs estimated $45 billion in 1989, or almost 2% of total wages earned by employees covered under workers' compensation. Physicians who have previously spurned the legal community, who scoffed at dealing with attorneys, or who refused to view their physician-patient relationships as adversarial should learn to embrace and nurture this potential service-contract opportunity.

Practitioners are constantly battling with the insurance industry to pay fees as billed, fighting the nuances of managed care and health-maintenance organization (HMO) programs, and coping with the customary and usual fee-for-service letters that reject bills and pay what the insurance industry believes the service is worth, not to mention the training and expertise required to provision of said service. Whatever terms are applied in a litigious setting (eg, forensic medicine, disability examinations, IMEs, FCEs), full 100% reimbursement for services rendered must be allowed. The future financial health of practicing clinicians may rest in the courtroom or administrative-law hearing room.

FCE systems

The most effective system for assessing disability in a forensic setting is the FCE protocol. This technique allows for the rating of impairment, as well as an examination of the person's ability to function in tasks, with standard norms simulating the mechanics of work.

Klimek and Strait (1997) and May (1993) characterized the purpose of the FCE to access and predict work behavior and vocational potential, as well as to match a given level of work performance to appropriate tasks with a margin of safety that reduces likelihood of reinjury. The applications are numerous in terms of workers'-compensation, personal-injury, or product-liability cases. One application is when an injured worker achieves MMI and the physician wants to know what work restrictions to document before releasing the patient from care.

The FCE can be used to document specific work tolerances and recommendations for the biomechanics of those tasks, detailing for the attending physician what restrictions should be applied. If a discrepancy exists between the physician's findings and the examinee's complaints, the FCE can offer evidence of the complaints and specific diagnosis based on repeated measures and/or testing techniques, psychometrics, and behavioral observations.

A comparative analysis of current FCE programs and instruction on how to perform an FCE are beyond the purpose of this section. Instead, a few of the FCE programs reviewed in the literature are presented below.

Several FCE protocols have been published, along with detailed reviews of their application in the FCE process (eg, Feuerstein, 1992; Hart, 1988; Hart, 1994; Matheson, 1988; May, 1984a; May, 1984b; May, 1988; May, 1993; Wickstrom, 1990). In 1984, May first described a protocol he developed on the basis of the Matheson model, which incorporated job analysis, work-simulation activities, materials-handling assessment, and testing of gross muscle strength. In 1988, documented the role and function of the staff members on the FCE team. Hart et al (1994) reviewed specific FCE components, including (1) recording the examinee's history, (2) conducting preevaluation screening, (3) performing functional-capacity testing, (4) interpreting the results, and (5) writing a report of the findings.

Isernhagen (1988) conceptualized the role of the physician in the FCE process with her assessment of the purpose of FCE, that is, to assess the examinee's maximum physical capabilities to arrive at a statement of the extent of the examinee's impairment. Therefore, her statement alone suggests the involvement of a multidisciplinary team to determine the person's functional capacity and resulting impairment.

Hart et al (1994) supports this team concept, noting that the FCE: "combines a comprehensive neuromusculoskeletal examination [physician, physio/occupational therapist working as one evaluation team] with measurements of physical impairment, symptom magnification/worker behaviors, and function and culminates with the measurement of the current functional abilities of the client."

The researched protocol with established construct validity is the one Dr Talmage Hiebert of the NADEP developed and which May and Martelli refined in 1999. The NADEP FCE model is predicated on the work-capacity evaluation (WCE) protocol that Dr L. Matheson of the Employment and Rehabilitation Institute of California researched and established.

One of the primary components this last FCE model, and all subsequent ones, is the analysis of materials handling and lifting.

This component is essential because most individuals referred for WCE have musculoskeletal injuries due to work-related lifting and falling accidents that culminate in orthopedic-related diagnoses. Therefore, the NADEP model must focus on documenting the functional integrity of a worker's materials-lifting and materials-handling capabilities to determine the most feasible work criteria for returning while maintaining acceptable safety and productivity.

Matheson developed the lifting protocol in the NADEP model by using the Work Evaluation System Technology (WEST) evaluation system (see Image 1). This lifting evaluation system is the one that the NADEP protocol incorporates because of Matheson's timely research into the safety and application of this component in the FCE process.

The WEST system was developed to evaluate the lifting capacity of workers who have had a variety of industrial injuries, using the full vertical work plane while gradually increasing the examinee's workload. The system is safe to administer and complies with the criteria for physical assessment measures t published by the National Institute of Occupational Safety and Health (NIOSH). Furthermore, Matheson established that the instrument is reliable on repeated-measures testing and that the results compare favorably with isometric measures of lifting capacity.

Despite its focus on materials handling, however, the NADEP Work Disability Evaluation Model incorporates 5 other components: (1) clinical interview and/or intake screening, (2) patient profiling, (3) work–vertical plane functional ROM/systems examination, (4) grip-strength testing, (5) static validity and/or reliability and dynamic strength tests, and (6) domain testing.

The 6 components that constitute the NADEP model are easily documented and calculated by hand. However, with the advent of computerized systems and evaluation software the NADEP model has become an expedient evaluation tool that can now combine impairment-rating coefficients in its summary interpretations. In this way, it can provide the referring source with a combined report on functional capacity and impairment rating.

The NADEP model is only one of many FCE protocols, and the reader is encouraged to review all the models published in the literature. The reader can find a multitude of FCE computerized systems that advertise complete, valid, and reliable FCE programs that can withstand the scrutiny of litigation. These systems sell the clinician on the concept that they are designed to save time and effort because the system performs all the calculations and presents the data in nicely ordered tables with bar or line graphics of the repeated measures.

The reader is cautioned not to place rely on these systems to complete the FCE in a valid and reliable manner. The FCE process and its administration are only as good as the examiner. The quality of the FCE administration and the interpretation of its results rest solely with the experience and training of the examiner and not with the equipment used.

Reliability and validity of FCE

The issue of reliability and validity in the FCE process remains, despite the quality of the computerized system or the preferred manual method. Although Babisky and Sewall identified reliability and validity issues in the impairment rating process, little data suggest that the validity and reliability issues associated with FCE have been resolved satisfactorily. King et al identified a lack of validity and reliability as a major concern in their review of 10 major computerized FCE systems, 8 of which are well known and accepted in the US marketplace. Only 2 systems achieved peer-reviewed interrater and intrarater reliability research, and associated peer-reviewed validity study was available for only 1.

Lechner et al similarly took issue with the lack of established reliability and the potential for abuse in interpreting results from the application of test components in FCE protocols. They reviewed application of the Waddell nonorganic signs, the coefficient of variation, and the interpretation of heart-rate fluctuations with incidences of pain and concluded that these components may be misinterpreted and/or unreliable for determining maximum voluntary effort in the FCE. Overinterpretation or misinterpretation may lead to false-positive results or to identifying the examinee as one who is magnifying symptoms or malingering or as one who may not be suitable for the competitive labor market.

An accurate assessment of a patient's willingness to exert maximal effort during FCE is critical to interpreting the results of the evaluation. In a study by Lemstra et al (2004), 90 patients with low back pain were evaluated for maximal effort during FCE. The tester's opinion on the patients' results on the maximal-effort tests had an overall specificity of 84.1% and a sensitivity of 65.2%. Only 5 of 17 commonly used maximal effort tests were individually useful in differentiate between maximal effort and submaximal effort. The authors concluded that caution should be exercise when one identifies patients as giving maximal or submaximal effort during FCE.

Little doubt exists that more research is needed in the disability-examination process, both in the medical field regarding IMEs and in the allied-health professions involved in FCEs. As King et al noted, the overall quality of the examination process hinges on the examiner's competence and specific training. Poorly training or inadequate preparation of evaluators can confound reliability and validity, perpetuating a rater effect in the testing protocol of the independent medical evaluation and FCE. The rater effect surfaces when results are extrapolated from the clinical examiner's personal biases or when the examination protocol is violated and its results are misinterpreted because of the examiner's lack of methodologic training.

Although the review by King et al was thorough regarding FCE equipment, they based their conclusions on the quality of the equipment rather than on the FCE process itself. As noted before, the solution for this dilemma lies in the evaluator's skill and training and not in the type of equipment chosen FCE. The NADEP maintains that rater error and that deficits in skill can be minimized by establishing a standardized or consistent evaluation protocol across all specialties complete with consistent terminology. The NADEP attempted to achieve this goal with its FCE-researched protocol.

Since the inception of the FCE process, numerous designers of evaluation equipment have striven to build the optimal system. First, they wanted to take advantage of the expanding need for systematic application of testing components to minimize the time required of the therapist, physician, or evaluator and thus enhance productivity. Second, they wanted to establish their vendor's company as a leader in equipment design and function. The market demanded not only user-friendly equipment for measuring function but also equipment that had undergone the scrutiny of reliability and validation in peer-reviewed studies.

As noted earlier, King et al reviewed the 10 FCE systems or equipment vendors that produce the most recognized FCE systems, 8 of which are from the United States or Canada and 2 from Australia. The Table below summarizes these systems.

Note.—King et al (1998) reviewed 2 Australian systems not well known in this country and therefore excluded from this table.

The literature about reliability and validity was reviewed for the Isernhagen Work Systems FCE, the Blankenship system, the ERGOS Work Simulator, and the Ergo-Kit. The search resulted in 77 potentially relevant references, but only 12 were included and assessed for methodologic quality.

The interrater reliability and predictive validity of the Isernhagen Work Systems FCE was good, though the procedure used in the studies of interrater (test-retest) reliability was not rigorous enough to allow for any conclusion. Reneman et al studied the test reliability of the Isernhagen Work Systems FCE. The test-retest reliability of the material-handling group was acceptable. Crude analyses of the ceiling and criterion tests revealed acceptable test-retest reliability of most, but not all, tests (Reneman, 2004).

The concurrent validity of the ERGOS Work Simulator and the Ergo-Kit was not demonstrated, and no study of their reliability was found. Likewise, no study was on the reliability and validity of the Blankenship system was found.

The conclusion was that more rigorous studies are needed to demonstrate the reliability and the validity of FCE systems, especially the Blankenship system, the ERGOS Work Simulator, and the Ergo-Kit (Gouttebarge, 2004).

Gross examined the validity of the Isernhagen Work Systems FCE in predicting timely return to work (Gross, 2004). He found that 4% of patients passed all Evaluation tasks, yet most had temporary total disability suspension and claim closure within 1 year after the FCE. Performance on the floor-to-waist lift was as predictive of the number of tasks failed in the entire FCE protocol.

Insurance carriers have questioned the validity of FCEs. In a review by Pransky, test criteria and the application of results were discussed (Pransky, 2004). The validity of FCE results was optimal with accurate job simulation and detailed, intensive assessments of specific work activities. When test criteria were unrelated to job performance, or when subjective evaluation criteria were used, the validity of the results is questionable. Reliability in a subject over time may be adequate to support serial FCE data collection to measure progress in worker rehabilitation.

Data from Harbin and Olson support testing after a job offer is made and before placement (Harbin, 2005). Strength testing alone was of no value in predicting the incidence of work injury, though physical capacity was strongly correlated with physical job requirements. Injury rates were lower in employees who had the physical strength or ability to perform the essential functions of their jobs than in those who did not. The incidence of low back injuries in workers with or without the physical capability to perform the required job functions was 3% or 33%, respectively. Results from physical-capacity testing in which lifting ability is compared with the lifting requirements of the job were correlated with the incidence of work injury. The application of appropriate postoffer, preplacement testing is a cost-effective method to lower the incidence of work-related injuries.

Gross discussed concerns about what FCE really measure (Gross, 2004). Although raters' judgments about a patient's maximum performance during FCE appear reliable, FCEs do not appear to be purely tests of physical capacity because many personal and environmental factors affect the patient's performance. FCEs are most accurately considered behavioral tests influenced by many factors, including physical ability, beliefs, and perceptions, and the results should be interpreted within the subject's broad personal and environmental context.

In a comparison of the ERGOS Work Simulator and the Ergo-Kit), researchers concluded that the concurrent validity for lifting between was poor for both FCE methods (Rustenburg, 2004).

In 2003, Geisser discussed the effect of psychosocial factors on FCEs, stating "Psychosocial factors have been found to have a significant impact on functional activity, particularly among persons with chronic pain. Although various systems have been developed to assess functional limitations through functional capacity evaluation (FCE), assessment of psychosocial factors that may impact function have been largely ignored. This paper examines the existing literature on psychosocial factors and FCE performance. Given that there are few studies that have directly addressed this issue, the paper also examines psychosocial factors that have been found to influence function in persons with pain. The results of the literature review indicate that few psychosocial factors have been found to be directly associated with FCE and functional measures, although many are related to various measures of disability.

The strongest evidence that psychosocial factors are related to functional performance is based on the studies examining the association between functional activity and pain-related fear, self-efficacy, and illness behavior. Psychosocial factors have also been shown to influence measures of sincerity of effort often obtained during FCE" (Geisser, 2003).

Perception of the patient also influences performance on FCEs. In 2005, Good, discussed factors that influence performance on FCEs. "Only the PDI (Pain Disability Index), pain intensity, age, and sex independently contributed to floor-to-waist lift performance. The PDI, pain intensity, and duration of injury contributed to the number of failed tasks. The results indicate that performance on FCEs is influenced by physical factors, perceptions of disability, and pain intensity. However, perceptions of workplace organizational policies and procedures were not associated with FCE results for workers' compensation claimants with chronic back pain disability. FCEs should be considered behavioral tests influenced by multiple factors, including physical ability, beliefs, and perceptions" (Good, 2005).

FCEs are behavioral assessments that are influenced by pain. Increased pain levels during and FCE can reduce performance levels. Therefore, pain factors must be taken into consideration when making predictions about future work status. Gross suggests that shorter FCEs be considered to address this effect (Gross, 2006).

Taking this into account, a short-form FCE was compared with the traditional FCE. Floor-to-waist lift, crouching, and standing were maintained in the short-form FCE. This limited evaluation was found to predict comparably with the entire FCE protocol in 2 validation cohorts (Gross and Battié, 2006).

Conclusion

The medical-service delivery system must adjust to the influences of managed care, HMO programs, and insurance capitation policies to control expenditures for medical benefits. Physicians must diversify into markets that they have not approached or even considered, given the current practice and business trends. The market for forensic services is thriving and seeks physicians to provide impairment ratings, IMEs, and FCEs to meet the escalating demand in personal-injury and product-liability litigation. The practicing physician may not know the FCE process, but it is one that effectively addresses the issue of disability and helps in identifying the functional deficits and capabilities of a patient with disability.

Almost as many manual disability-evaluation protocols exist as computerized disability-evaluation systems. The clinician is cautioned to approach FCE practice by first choosing a protocol that meets the scrutiny of the judicial system and by then selecting the FCE system that is flexible in accepting the chosen FCE protocol.

IMPAIRMENT RATING GUIDES

Section 4 of 11

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Authors and Editors
Introduction To Impairment And Disability Evaluation
Concepts In Disability Evaluation
Impairment Rating Guides
Impairment Rating Examples
Example Of Disability Evaluation
Legal And Other Issues Of Impairment Rating And Disability Evaluation
Psychiatric Issues Of Impairment Rating And Disability Evaluation
Sample Deposition Questions On Impairment Rating And Disability Evaluation
Multimedia
References

Many states and jurisdictions have statutory requirements requiring the use of specific evaluation systems or guides to determine a permanent impairment rating (PIR) due to accident or injury. Some systems incorporate a disability schedule to supplement or complement the impairment-rating schedule. Many states place restrictions on which clinicians can provide impairment ratings. In Florida, for example, chiropractic physicians may issue ratings, but psychologists may not.

Although the American Board of Medical Specialties (ABMS) currently does not provide certification in impairment and disability evaluation, other organizations do. Certification for impairment rating may be obtained from the NADEP and the American Academy of Disability Evaluating Physicians (AADEP). These organizations provide education, training, and certification in impairment rating and related issues. Both organizations provide instruction by physicians and other healthcare professionals about impairment and disability-related issues.

Although certification is not required, if the healthcare professional foresees performing a substantial number of impairment rating evaluations, attendance at courses on the evaluation process is suggested. Disability medicine is the most likely of all areas of medicine to involve attorneys. Completion of a training course with certification by the AADEP or the NADEP increases the likelihood of a successful forensic experience.

Examples of guides include the following: the AMA Guides to the Evaluation of the Evaluation of Permanent Impairment, 5th edition, 1999 (order from the AMA), the 1996 FUPIRS, the Minnesota Disability Schedule, and the California Workers' Compensation Rating System.

Some states permit physicians to render impairment ratings based solely on their own experience and observation. This system presents a classic dichotomy between statutory permissiveness and scientific reliability (see Daubert v Merrell Dow Pharmaceuticals, Inc, 509 US 579 (l993).

IMPAIRMENT RATING EXAMPLES

Section 5 of 11

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Authors and Editors
Introduction To Impairment And Disability Evaluation
Concepts In Disability Evaluation
Impairment Rating Guides
Impairment Rating Examples
Example Of Disability Evaluation
Legal And Other Issues Of Impairment Rating And Disability Evaluation
Psychiatric Issues Of Impairment Rating And Disability Evaluation
Sample Deposition Questions On Impairment Rating And Disability Evaluation
Multimedia
References

Impairment ratings have been calculated by using 2 systems. Eleven case examples and solutions are included here as examples. For specific cases, actual guides must be used. Further resources can be found at WorkersCompensation.com, where Florida's system is discussed extensively.

A 37-year-old right-handed worker presents with impingement syndrome of the left shoulder. Examination of the left shoulder shows moderate crepitation with limited active ROM (AROM), as follows: left shoulder flexion 100°, abduction 90°, internal rotation 60°, and external rotation 60°. Radiography shows arthritic changes in the acromioclavicular joint of the left shoulder. MRI shows impingement of the left shoulder (referred to here as the UE).

A 35-year-old right-handed man presents with right shoulder impingement after arthroscopic surgical acromioplasty (ie, arthroplasty). Examination shows a tender subdeltoid region with slight pain and constant moderate crepitation during AROM. The patient has full active and passive ROM. (Note: Calculations are performed with and without the surgical option.)

A 25-year-old male worker presents with chronic left lateral epicondylitis. He is left handed, and his condition has failed to improve with conservative treatment. He has not undergone surgery. Examination shows mild painful crepitation in the left lateral epicondylar region. AROM of the left elbow is noted with extension 0°, flexion 130°, pronation 70°, and supination 80°. Radiography of the left elbow shows calcification of the lateral epicondylar region.

A 40-year-old right-handed woman presents after undergoing surgery in the right wrist for carpal tunnel syndrome. Examination shows normal motor strength with manual muscle testing of the right hand, including median nerve innervated muscles. Sensation is reduced, which interferes with activity of right median nerve distribution. EMG shows mild dropout of motor units with needle electrode findings in right abductor pollicis brevis, not first dorsal interosseous. Nerve-conduction study (shows mild slowing and right median sensory distal latency.

A 65-year-old man presents with moderate degenerative joint disease of the right hip after hip fracture. Examination shows mild antalgic gait, and the patient uses a cane for only outdoor ambulation. AROM of the right hip is normal, and the right leg is 1 in. shorter than left. Radiography shows moderate degenerative joint disease with a 3-mm cartilage interval for the right hip.

A 40-year-old woman presents with chronic bursitis of the greater trochanter of the right hip. Examination shows local tenderness with a trigger point at the right greater trochanter. Full active and passive ROM of the hip demonstrates pain reproduction on resisted abduction and an antalgic gait in the right LE if she walks longer than 30 minutes. The patient does not require the use of an assistive device.

A 25-year-old man presents with a tear of the medial meniscus tear in his right knee after partial medial meniscectomy. After rehabilitation, he continues to have knee pain, locking, swelling, and mild effusion. Examination shows that AROM of the right knee is 0° (full extension) to 130° flexion. Strength on manual muscle testing is grade 4/5 (extension/flexion) for the knee. Atrophy is 2 cm in the right calf and thigh compared with the left, and his gait is antalgic on the right leg. Radiographs show moderate degenerative changes of the right knee with a 3-mm cartilage interval.

A 62-year-old woman presents with a knee injury, aggravating severe degenerative joint disease of the left knee. Patient has undergone left total knee arthroplasty with no pain after surgery. She has stable anteroposterior and mediolateral motion. She has no flexion contracture, no extension lag, and normal alignment. Examination shows well-healed left knee surgical scar, mild effusion of left knee, and left knee AROM/passive ROM (PROM) of 0-100°. Patient can ambulate with routine use of cane but does not require a brace. Radiography shows left total knee arthroplasty.

A 45-year-old right-handed woman presents with history of severe stretch injury in the left brachial plexus. She as residual, severe reflex sympathetic dystrophy of her left arm, with causalgia and complex regional-pain syndrome. Examination shows an atrophic left arm and forearm with cold, clammy, dusky, shiny skin. No AROM is noted at the shoulder, elbow, wrist, or hand. PROM shows clinically significant guarding, but it is generally restricted. Contractures are noted in the shoulder, elbow, wrist, and hand, but the examiner cannot establish consistent measurements with a goniometer because of guarding. Pulses are +2 and equal for both radial and ulnar arteries.

No voluntary motion more than trace motion is noted in the patient's entire left UE. Sensation is noted in the left UE, with hyperpathia and allodynia. EMG and nerve-conduction studies are performed. EMG of the left arm shows decreased insertional activity and poor recruitment of motor units. Nerve-conduction study of the left arm is impossible of pain. Radiography shows evidence of osteopenia in the left arm.

A 29-year-old man presents with chronic lumbosacral strain, no numbness or weakness of LEs, and no loss of bladder or bowel function. Examination shows spasms and rigidity on palpation in the lumbosacral paraspinal muscles. Restricted flexion-extension lumbosacral ROM is noted, but readings are inconsistent with those obtained with an inclinometer or goniometer. Neurologic examination of the lower extremity is normal, showing no weakness or atrophy. Deep tendon reflexes are normal with no sensory loss. Radiographic and MRI findings in the lumbosacral spine are normal.

A 45-year-old man with L4-5 herniated nucleus pulposus presents after single-level laminectomy, discectomy, and fusion surgery. His symptoms include continued back pain and sciatica of the right leg. Numbness noted in the L5 distribution of the right leg does not interfere with his function. Mild weakness of the right leg is noted, but the patient can ambulate without use of cane. He has difficulty sleeping because of pain when he lies supine.

Examination shows rigidity and a surgical scar over the lumbosacral region. AROM/PROM of the thoracolumbosacral spine in all planes are normal, though values on straight-leg raising and inclinometry are inconsistent. On straight-leg raising, positive findings are noted on the right side are in the when the patient is supine but not when he is seated. Strength of the right great toe and right ankle dorsiflexor is 4/5, no atrophy of the calf musculature is noted.

Testing of the deep tendon reflexes an absent right medial hamstrings reflex. Sensation is decreased to pain in the right L5 distribution. Gait analysis shows an antalgic pattern in the right leg. Presurgical radiography of the lumbosacral spine shows spondylosis at L4-L5. Presurgical MRI shows herniated nucleus pulposus at L4-5 on the right. After surgery, lumbosacral MRI shows evidence of gad fusion and scarring at L4-L5. EMG shows active right L5 radiculopathy before surgery and chronic, mild right L5 radiculopathy after surgery.

No additional impairment is added for disturbed sleep because of pain or discomfort in supine position. No impairment is included for fusion with loss of ROM of the lumbosacral spine.

EXAMPLE OF DISABILITY EVALUATION

Section 6 of 11

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Authors and Editors
Introduction To Impairment And Disability Evaluation
Concepts In Disability Evaluation
Impairment Rating Guides
Impairment Rating Examples
Example Of Disability Evaluation
Legal And Other Issues Of Impairment Rating And Disability Evaluation
Psychiatric Issues Of Impairment Rating And Disability Evaluation
Sample Deposition Questions On Impairment Rating And Disability Evaluation
Multimedia
References

The following case study is from a FCE by using the NADEP protocols. The testing components of this particular example include intake patient screening, grip-strength testing, ROM and strength studies, and dynamic-lifting evaluation. These components were observed as May and Martelli outlined and emphasize the need for the examining physician to review all physiologic aspects, as well as the potential psychological response.

This history was collected during intake screening, the first component of the model.

The examinee had an open, grade 3C fracture left tibia due to a fall at work. He was immediately transported to a trauma center. He underwent irrigation and debridement of the left ankle and external fixation of the left distal tibia. He remained in the hospital for approximately 1 week. He stated that he was given instruction on how to use crutches before he was discharged. He was advised to return to his orthopedic physician for follow-up and treatment on a weekly basis. This schedule continued for approximately 4 months, and then he saw his orthopedic surgeon once a month.

During the 4-month period, he was hospitalize twice for additional surgery: repeat irrigation and debridement of the left tibial pilon fracture with closure of the ankle wounds took place and later open reduction internal fixation of the left distal tibia and irrigation and debridement of the medial ankle wound with removal of the external fixator.

The patient then began formal physical therapy and aquatic therapy. At present, he is continuing home aquatic therapy by using the pool at his local YMCA. He will next begin therapy to evaluate progress with his home program with a visit schedule of once a week.

The patient's medications are celecoxib (Celebrex) 100 mg bid and acetaminophen and hydrocodone (Lortab 500/7.5 mg). He states that he had no prior medical injuries or disabilities related to his work or personal life.

Additional information that is collected but not reported here included the patient's educational level, family history, support system, financial situation (ie, whether he receives disability income or whether he has no income [The amount is not important.]), and vocational history in the previous 15 years.

The examiner administers the second component, patient profiling. At this point, the examiner learns how the patient is coping with his disability, how well he has adjusted to the disability period, if the patient is exaggerating symptoms, and if the individual is reporting systemic or localized profile.

The patient completes a symptom chart (see Image 2). (This chart is specific to the injury and locations of any surgical incisions, and it presenting a localized profile.) The information is encouraging because it suggests that the patient has some control over his symptom-response patterns in response to daily activities and that no other anatomic locations are involved. The patient's rehabilitation potential may be good, but no opinion can be given confidently without a review of all profiling and functional data. Reviewing the form in Image 2 can help in identifying a possible trend.

Image 3 shows the changes in activity rating. As much control as the symptom chart suggested, the patient's activities indicates a more substantial effect of his disability. The findings are this chart a notable, and suggest that the effect on his activities is directly related to the diagnosis. Had the patient described substantial changes in the first 2 senses (ie, hearing and vision), the examiner would flag this complaint as a possible sign of exaggeration of symptoms. One item that was not expected was the last one, material handling. This finding should alert the examiner to look for significant deficit profiling in the remaining test activities, as this item was not related to the affected area and/or diagnosis.

Image 4 graphically depicts the patient's symptomatic response to physical activities as he progresses through the evaluation process. His pretest, resting discomfort levels are documented, and his performance and behavior are monitored from that point until the end of the last test item. The patient demonstrated some control and management of symptoms until he engaged in the dynamic lifting and carrying activities, which stressed his affected extremity the most.

At this point, the patient's response to the activities, his ability to participate in the test activities, and his overall functional responses are summarized in the report.

"To summarize, Mr. [Examinee] demonstrated an ability to negotiate his symptoms, or an ability to manage and control his symptoms until functional activity was applied to his lower extremity. He exhibited mechanical/strength deficits in ROM and dynamic activities. Regarding the dynamic lifting study, he completed the WEST lifting evaluation but the crate carrying activity was waived due to his lower extremity weakness and mechanical dysfunction. Based on the medical records and the Examinee's performance on this functional study, it is this evaluator's opinion that the Examinee can function independently in the competitive labor market without accommodation at the LIGHT physical exertional demand level. He requires accommodation when functioning at the MEDIUM to HEAVY physical demand levels."

The next component is the grip-strength study. The graph in Image 7 shows a good, symmetric strength pattern between the right and left hands. This component is not used to investigate strength output. Instead, this component helps the examiner obtain an impression of how the patient will perform during the rest of the examination. Will he or she be inconsistent? Will he or she display overt pain behaviors when engaged in activity? Will he or she complain of unrelated symptoms? In this case, the examiner can conclude that the patient had a good effort, given the symmetric output of the patterns and that repeated measures were within acceptable variances.

The next component is the ROM and systems review and physical examination when the patient is measured for joint ROM and strength in the UEs and LEs. The patient undergoes thorough musculoskeletal and neurologic examination.

This examinee was tested for strength discrepancies between the affected and unaffected legs. Repeated measurements were collected to determine the reliability of data among trials. Images 10-11 show his strength output. The patient's left LE, the affected extremity, constantly performed at a level below that of the right. His repeated demonstrated good reliability of effort between and among trials. Because no normative data exist, the examiner used this technique to determine the patient's consistency of performance and to document any notable strength deficits.

Images 10-11 show how the tests were administered. In the NADEP model, these digital images are used in reports, for obvious reasons. Because forensic disability is being assessed, attorneys from both sides need to know what was done and how the data were collected.

Next is the static strength component, which was not performed in this case study. Because strength data were obtained in the ROM component, this one was waived.

The final component is dynamic lifting. Domain testing was not administered because the examiner already had sufficient data to render an opinion on the patient's work capability. Therefore, work-simulation activities were not necessary.

In the dynamic-lifting component, stationary lifting system (WEST Evaluation System) was used. Before dynamic study, the patient's lifting mechanics and his maximum lifting weight were determined by using the pretest lifting-evaluation protocol May and Martelli cited (1999). The patient was observed to compensate for his mechanical deficits (Image 12). He holds his left leg higher than his right, suggesting that his weight-bearing capacity is greater on the right leg than on the left. Images 13-14 show his maximum upper and lower lifting ranges. The examiner is looking for any compensatory mechanics on these images.

Image 15 shows the swelling in the left LE that the patient reported as being problematic in his functioning and overall symptom response.

Images 16-17 demonstrate the patient's cumulative lifting in terms of the weight carried in foot-pounds, as well as his heart rate and blood pressure before and after the test. This information is crucial because it documents the patient's effort the in the lifting exercises and his vital-sign responses. For example, if the patient's heart rate does not increase and if he or she demonstrates substantial pain and response, the examiner suspect the person's overall effort in the test. The patient in this case demonstrated good effort.

Images 5-6 show the method for summarizing the examinee's functional performance, including how his performance was documented and what competitive functional levels are recommended. Image 6 shows a summary if his dynamic lifting/materials handling capabilities. In this case, the examinee was rated being as capable of performing lifting considered in the heavy category, but only with modifications to his work setting, specifically, to his vertical work plane.

Conclusions are summarized under the NADEP heading vocational implications. This section indicates the physical demand level or characteristic, as the US Department of Labor defines it. In this, case the rating for physical demand characteristic was awarded from the restricted and unrestricted vertical and/or horizontal work planes.

The final comments address workplace considerations. Here, the examiner outlines the specific physical activity restrictions, such as those applied to bending, kneeling, stooping, standing, walking, and climbing. The individual's likelihood of being placed in a suitable job and his or her overall likelihood of employment may be addressed as well.

Based on the US Department of Labor definitions for WORK and accompanying physical exertion demand levels, it is this examiner's conclusion that the examinee qualifies for the HEAVY work category within the restricted work plane, provided that the work criteria, as presented in Tables 1 and 2, are integrated into any return-to-work considerations. When considering the competitive unrestricted vertical and horizontal work planes, the examinee qualifies for the LIGHT work category.

Mr. Chenault manipulated weight at a level that qualifies him for the HEAVY physical demand characteristic under the Department of Labor definition of work. However, what this resistance level does not detail is his lack of tolerance and stability for moving this weight level from point "A" to point "B". His left lower extremity demonstrated significant atrophy when circumference measurements were taken and his strength patterns were significantly weaker than the right. Thus, while he can manipulate a maximum of 50 pounds from a standing position, this is not a true measure of work performance, or the ability to manipulate the weight in terms of carrying and stacking. Thus, it is highly recommended that Mr. Chenault be removed from activities that require repetitive kneeling, stooping, squatting/crouching, walking and climbing stairs and/or ladders.

This gentleman would benefit from an active job placement and development program at this time, as he should begin focusing on return-to-work options and strategies. I conclude that his returning to carpentry work or related fields with similar work demands is poor and guarded at best, regardless of physical rehabilitation efforts. He is a highly motivated individual and I strongly believe that he wants to become gainfully employed as soon as possible.

LEGAL AND OTHER ISSUES OF IMPAIRMENT RATING AND DISABILITY EVALUATION

Section 7 of 11

�

Authors and Editors
Introduction To Impairment And Disability Evaluation
Concepts In Disability Evaluation
Impairment Rating Guides
Impairment Rating Examples
Example Of Disability Evaluation
Legal And Other Issues Of Impairment Rating And Disability Evaluation
Psychiatric Issues Of Impairment Rating And Disability Evaluation
Sample Deposition Questions On Impairment Rating And Disability Evaluation
Multimedia
References

Questions

Case law discusses a PIR as an anatomic or functional abnormality or loss that a physician establishes and rates. (Escambia County Council on Aging v Goldsmith, 500 So2d 626 [1st DCA l987]). Judges and courts throughout the nation have generally accepted this definition.

In the worker's-compensation system in Florida, as in many other states, impairment ratings determine specific benefits the claimant can receive. For example, a 7% PIR may mean that the claimant receives benefits for 7 weeks. The Florida Supreme Court has upheld the fact that benefits are tied to impairment ratings and not disability (Bradley v Hurricane Restaurant, 670 So2d l62 [Fla l996]).

The PIR can originate only from a compensable injury (Murphy v NE Drywall, 692 SO2d 9l8 [l997]).

Medical doctors, osteopathic physicians, chiropractic physicians, optometrists, dentists, and psychologists can make PIRs. Some states, such as Florida, restrict the medical specialists who may assign ratings.

Yes. Ratings are usually based on both objective and subjective information. Subjective complaints include pain, numbness, and depression. The practitioner cannot ignore these complaints when determining an impairment rating.

The best example of the use of scientific evidence is found in the case of Daubert v Merrell Dow Pharmaceuticals, Inc, 509 US 579 (l993), which demonstrated that certain factors may bear on the judge's determination about the admissibility of scientific data. Considerations included (1) whether a "theory or technique can be (and has been) tested"; (2) whether it "has been subjected to peer review and publication"; (3) whether, in respect to a particular technique, the "known or potential rate of error" is high and whether "standards controlling the technique's operation" are established; and (4) whether the theory or technique enjoys "general acceptance" within a "relevant scientific community" (509 US at 592-594). The Federal Rules of Evidence, as well as many state courts, have adopted this decision.

The US Supreme Court recently extended the Daubert philosophy to nonmedical experts (Kumho Tire Company, LTD, et al, Petitioners v Patrick Carmichael et al, 526 US l37 [l999]). The fact that a practitioner assigns an impairment rating does not mean that it is admissible. The rating must be scientifically based and must rely on a disability guide with a proven record.

The impairment rating should occur at MMI, the point at which further recovery from or lasting improvement too an injury or disease can no longer be anticipated on the basis of reasonable medical probability. The PIR is given when the claimant has an injury (Murphy v NE Drywall, 692 SO2d 9l8 [l997]).

The examiner should not wait rating until after completing all reports to document an impairment. By then, it may be too late.

A recent decision precluded an expert from testifying about to PIR on the witness stand (Auto Owners Insurance Co and Roberts v Clark, 676 So2d 3 [4th DCA 96]). In this case, the court held that the neurosurgeon could not give testimony regarding an impairment rating because his observations would have been based on a treatment session after the cutoff date for discovery. This ruling is intended to prevent 1 party from having an unfair advantage of surprise over the other.

For example the defense team hires an examiner who renders a report, the plaintiff prepares for the hearing on the basis of the contents of the report. If the examiner arrives at trial and changes his or her diagnosis, the judge may strike all of the testimony as being inconsistent with the initial report if the examiner's testimony is a surprise and if it was developed after the cutoff date for discovery.

In a forensic environment, when FCEs are frequently used, scientific nature of the test may be questioned.

The decision of the United States Supreme Court in Daubert v Merrell Dow Pharmaceuticals, Inc, 509 US 579 [1993] and progeny, in conjunction with Federal Rule of Evidence 702, define the Court's gatekeeping function in relation to the admissibility of proposed scientific and other expert testimony.

Rule 702 states, "If scientific, technical, or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue, a witness qualified as an expert by kno