Development and construct validation of the Hand Function Sort.

The construct validity of the Hand Function Sort (HFS) was investigated in 126 adults of working age (65% male) with medical impairments. Principal components factor analysis identified one major factor and two minor factors, which was consistent with the findings of a subsequent Harris Image Analysis. A Kaiser Image Analysis identified seven factors, partitioning the first global factor. Construct validity also was studied. HFS scores of subjects who had impairment of the dominant upper extremity were compared with subjects whose dominant upper extremities were not impaired. Significant differences were found between groups for total scores and in categories of tasks for which hand dominance was likely to be important. Conversely, there were no significant differences with tasks for which hand dominance was not important. HFS scores were compared with grip strength, which accounted for significant variance in the total HFS score. When categories of tasks were considered, substantial variance in the factors for which grip strength was important was accounted for by grip strength. For tasks in which grip strength was not likely to be important, variance accounted for by grip strength was negligible.

Disability methodology redesign: considerations for a new approach to disability determination.

Disability determination meets important societal needs, involving billions of dollars and millions of people every year. However, disability determination decisions often are incorrect, and the high proportion of decision appeals and reversals creates additional administrative expense and difficulty for the people that the disability determination system is intended to support. Projects funded by the United States Social Security Administration explored these issues and developed new conceptual models and tools to improve the accuracy and fairness of disability determination. This paper provides an introduction to the projects and the papers in this special issue of the Journal of Occupational Rehabilitation.

Development of new methods to determine work disability in the United States.

The development of new methods to determine work disability for the United States Social Security Administration is described, including the fiscal and administrative background to the current and proposed methods. An introduction to the current disability determination process and description of its status is followed by a description of the original proposed plan for redesign of the process. In response to this plan, the authors participated in several research projects. An overview of some of the key research projects performed to improve the Social Security Administration disability determination process is provided.

Development of the Functional Assessment Taxonomy.

The development of the Functional Assessment Taxonomy is described and the taxonomy is presented. The taxonomy provides a method to classify and organize constructs that are used to assess the functional abilities of people with medical impairments to determine work disability. The taxonomy has 131 constructs that are organized into 33 conceptual factors that are nested in 5 domains. Each construct is defined and is categorized in terms of the work disability model and the unit of analysis that is commonly used to measure the construct. The use of the taxonomy in the Disability Methodology Redesign Project is described. Other possible uses for the taxonomy are presented.

Development of a database of functional assessment measures related to work disability.

The development of the Functional Assessment Measures Database is described. The database provides a method to organize and search for measures that are used to assess the functional abilities of people with medical impairments to determine work disability. The project identified 4,200 different measures that are used in the functional assessment of persons with disability across the life span, 812 of which are used to evaluate adults in terms of work disability. The database has 3,033 scales that are found in 633 measures. In the database, each measure is described and is linked to at least one functional assessment construct. The use of the database in the Social Security Administration Redesign Project is described. Other possible uses for the database are presented.

Restorative exercise for clinical low back pain. A prospective two-center study with 1-year follow-up.

STUDY DESIGN: A comparison of treatment of 412 patients with chronic back pain at two separate centers using the same treatment protocols and outcome measures. Outcome was defined by specific strength testing; Short Form-36 scores at intake, discharge, and 1-year follow-up; self-appraisal of improvement at discharge and in a 1-year follow-up; and reuse of health care services after discharge. OBJECTIVES: To investigate the efficacy of standardized treatment methods using isolated lumbar strength testing and strengthening based on progressive protocols using specific equipment. Comparison of results should clarify the effect of the treatment center versus the efficacy of standardized protocols. SUMMARY OF BACKGROUND DATA: There has been little support in the scientific literature for exercise programs based on standardized protocols. The use of specialized equipment to achieve intense specific exercise also has been poorly supported. Overall health benefit has not often been related to specific improvement in strength. METHODS: More than 400 individuals with chronic back pain were evaluated at the initiation of treatment, discharge, and 1 year after discharge. Measures of efficacy were based on Short Form-36 scores, self-appraisal of improvement, and reuse of health care services after discharge. Study participants were patients with chronic back pain consecutively referred to each treatment site and underwritten by a variety of payers, including workers' compensation, Medicare, and private insurance. RESULTS: Overall response during the course of the program and at 1-year follow-up was similar between the two centers. Similar proportions of participants at each site demonstrated improvement in SF-36 scores, self-appraisal of improvement, and reuse of health care services. CONCLUSIONS: Standardized protocols using specific strength and measurement equipment can achieve similar benefits at different sites.

Rehabilitation ergonomists: standards for development.

Ergonomics, in the traditional definition, is the science of design of work sites and work methods which influence production performance. In recent years, worker complaints and reports of injuries have caused evaluation of the effect of work stressors on workers. Currently, the rehabilitation specialist plays a pivotal role in both prevention and management of physical work related complaints. Rehabilitation ergonomic practitioners combine a scientific background in function and pathology with the act of developing preventive or restorative remedies. A volunteer group of sixteen rehabilitation professionals who utilize ergonomic principles in the workplace developed a document, identifying job functions of the newly defined field. This paper presents philosophy and a model for educational development and potential credentialing areas for rehabilitation ergonomists.

Impact of the Dayton Tire case.

Three of the more pertinent legal cases in the United States concerning the performance of ergonomists are summarized. The results of the cited cases have impact on the validity of the NIOSH lifting formulae, the lack of scientific evidence relating performance of jobs with alleged ergonomic stressors with specific medical pathology, and the gold standard for expert witness testimony. The cases, taken together, should act as a catalyst for ergonomists to improve their level of scientific justification for their work and conclusions.

Relationships among grip strength, work capacity, and recovery.

The relationship between strength, fatigue, and work capacity is a central issue for occupational rehabilitation. Musculoskeletal impairments often are expressed functionally as a loss of strength. For work tasks that require strength, such impairments may have a detrimental effect on work capacity that is sufficient to be disabling. How important is strength as a component of work capacity? How do work capacity and strength affect recovery time from repetitive forceful upper extremity work ? A sample of 40 healthy subjects comprised of 20 males and 20 females was studied in a model that used the isotonic strength of each subject to set exercise levels for subsequent forceful repetitive gripping tasks. Resistance levels of 75%, 50%, and 25% of maximum were used for one-per-second repetitions until the subject could not maintain that pace. Isometric grip strength was measured after 1 minute of rest and after 5, 10, and 20 minutes. Results indicate that males and females do not differ in terms of their rate of recovery and that the best predictor of recovery time is the immediate measurement of strength loss following cessation of work activity.

Relationships among age, body weight, resting heart rate, and performance in a new test of lift capacity.

This study measured the relative contributions of age, gender, body weight, and resting heart rate to lift capacity in 531 healthy employed males and females in a cross-sectional model. The objectives of this study were to measure the contributions to lift capacity that are made by these variables and to develop an appropriate means to express the results of a new test of lift capacity. A formal training program was developed and administered to 110 health care professionals. Subsequently, each trained evaluator performed five tests on healthy volunteers. The effect of the independent variables were studied through the use of multiple regression and analysis of variance procedures. Results indicate that age, resting heart rate, and body weight are significant predictors of performance, with the last variable being the most important. A method to normalize lift capacity is presented in which the maximum acceptable weight lifted is divided by the evaluee's body weight to derive relative acceptable weight, a variable which is normally distributed. Those who use measures of lift capacity to describe performance must consider the effect of these variables in order to make valid interpretations of lift capacity test performance.

Standardized evaluation of work capacity.

A standardized method of evaluation of the work capacity of persons who are impaired by soft-tissue injuries is described. A demonstration project which involved testing 64 impaired subjects is described. The Cal-FCP test battery can be administered independently by a properly trained professional or by a technician under a physician's supervision and requires two hours or less to complete. This study demonstrated that the results of the test battery are unbiased in terms of both gender and age and can be applied to a standardized disability rating system.

A test to measure lift capacity of physically impaired adults. Part 1--Development and reliability testing.

STUDY DESIGN: Two laboratory studies and one field study evaluated the safety and test-retest reliability of a new test of lift capacity. The first two studies were conducted in a carefully controlled laboratory setting. The first study investigated the safety and intra-rater reliability of the EPIC Lift Capacity test protocol with healthy adult subjects. The second study assessed the safety and inter-rater reliability of the test with disabled subjects. The third study was conducted in the field with 65 evaluators and investigated the safety and intra-rater reliability of the test with healthy adult subjects. OBJECTIVE: To assess the safety and reliability of a new test of lift capacity. SUMMARY OF BACKGROUND DATA: A new test of lift capacity has been developed. Test development occurred within the context of ergonomic standards and guide-lines of the major professional associations and public agencies that govern test development in the United States. METHODS: In study no. 1, 26 healthy subjects participated. In study no. 2, 14 disabled subjects participated. In study no. 3, 318 healthy subjects participated. After subjects underwent basic screening and warm-up, the EPIC Lift Capacity test was administered. One to 2 weeks later, the test was administered again. Correlations between the times of testing were calculated. RESULTS: No subjects were injured. Hamstring soreness the next day that resolved without complication was reported by some healthy subjects. None of the disabled subjects reported new symptoms. CONCLUSION: The safety and reliability of the EPIC Lift Capacity test was adequately demonstrated in a laboratory setting and across multiple field sites with evaluators who have varying types and degrees of professional preparation.

A test to measure lift capacity of physically impaired adults. Part 2--Reactivity in a patient sample.

STUDY DESIGN: Test reactivity is the based on the idea that experience with a test may affect performance on subsequent tests, independent of what the test purports to measure. The reactivity of a test of lift capacity was studied in a single-blind randomized clinical trial was studied in a single-blind randomized clinical trial in which subjects were assigned to one or two groups. One group received lift testing before and after a therapeutic trial, while the other group received lift testing only at the conclusion of the therapeutic trial. OBJECTIVE: To measure the reactivity of a lift capacity test over the course of treatment. SUMMARY OF BACKGROUND DATA: The reactivity of a test is an important criterion by which an outcome measure must be judged. Change in response to treatment is assumed to be independent of changes resulting from the evaluee's experience with the test, although this is rarely addressed. METHODS: The EPIC Lift Capacity test was administered to 55 patients with low back pain in a treatment program after they were randomized into a pre-test/post-test and a post-test only group. Additional measures were taken on a pre-test/post-test basis for all subjects. RESULTS: Analyses of variance demonstrated no difference between the randomized groups after treatment. However, the pre-test/post-test group demonstrated significant improvement over the course of treatment. Other measures of outcome were similarly affected. CONCLUSION: The reactivity of the EPIC Lift Capacity test was negligible over an 8-week treatment regimen that did not include lifting tasks.

Workers' compensation managed care: Preliminary findings.

The cost of providing care that is effective to return injured workers to the workplace has risen in recent years in a manner that appears to be out of control in the workers' compensation system. In turn, medical care costs are an important component of the rapidly increasing costs of workers' compensation insurance. A model of health care delivery that emphasizes early intervention and return to work is presented. This model focuses on providing aggressive treatment of injuries that historically have been reported to be extraordinarily expensive. This paper is a case study of a managed care treatment model and presents costs of treatment in the first year of utilization. Medical care costs of 295 cases are compared with state and national figures and are found to be substantially better, especially with regard to soft tissue injuries and injuries that involve days lost from work.

Guidelines for functional capacity evaluation of people with medical conditions.

Functional capacity evaluation is an important and widely available service provided by rehabilitation professionals, including many physical therapists. In the absence of agreed-upon professional standards, guidelines for practice have been developed. These guidelines provide a basis for the development of standards of practice which the authors believe should be undertaken on an interdisciplinary basis. These guidelines provide a baseline level of care that should be maintained by physical therapists and others who provide functional capacity evaluation services.