Disability assessment medicine

Impairment and disability

The two basic concepts of impairment and disability are important in understanding the role of disability analysts. The World Health Organisation defines impairment as “any loss or abnormality of psychological, physiological or anatomical structure or function.” This is largely a medical definition and is usually subject to some form of objective measurement, but it does not provide much information about how a particular individual is affected.

Disability, on the other hand, is defined as “any restriction or lack (resulting from impairment) of ability to perform an activity in the manner or within the range considered normal for a human being.” The concept of disability requires an assessment not simply of what is wrong with a person but also into what the person is prevented from doing. People with similar impairments may have very different degrees of disability. For example, people with identical leg amputations often have markedly different walking abilities. This largely medical model of disability contrasts with the “social model,” which sees disability more as a function of the environment in which the person operates. The terms activity and participation, with their more positive connotations, are increasingly preferred to the term disability.

Consistency and consensus

Consistency of behaviour across functional capacities is a well established clinical principle(1) and is a cardinal feature of disability analysis, particularly of subjective impairments. Impairment of any kind should have consistent effects regardless of the setting. The concept of consensus in this context refers to the need for an explicit recognition of medical opinion, based on research evidence wherever possible, about the clinical pattern of the disease. Rigorous evaluation of different medical opinions about a case, drawing on published evidence, analytical skills, and professional judgment, are the hallmarks for establishing consensus.(2)

Role of disability analysts

The role of disability analysts is to help decision makers reach fair and proper decisions, for example, on entitlement to cash benefits and provision of services or environmental adjustments that might be required. They do this by providing advice that is objective, clear, and capable of answering questions posed by a decision maker without compromising any subsequent adjudication process.

Increasingly, disability analysts are being required to assess functional capacity as much as incapacity. A person's performance may be influenced by the actual loss of function (such as by physical limitation), restrictions on function (such as advice not to perform certain activities), premature termination of activity, and suboptimal performance (possibly limited by pain and fatigue, environment, motivation, and attitude). The approach is increasingly to combine the medical and social models so that, overall, disability is seen to depend not only on bodily or mental impairment but also on performance and behaviour. Thus “ability” may be set by physiological or pathological limits, whereas actual performance is often set by psychosocial limits including the limits set by the person's specific environment.

Areas of work

The single largest area of work for disability analysts is in relation to social security benefits, such as state incapacity benefits, industrial injuries disablement benefit, and disability living allowance. Most full time doctors who carry out these assessments are now employed by the private sector, which provides services under contract to the Department of Social Security Benefits Agency. More senior and experienced disability analysts will be responsible for training part time doctors and monitoring the quality of their work.

Doctors who sit on appeals tribunals are often required to use the skills of the disability analyst, either in carrying out their own assessment of the client or by assessing the information provided by a medical disability analyst. Occupational physicians are often called on to apply the principles of disability analysis when providing advice to employers in relation to management of workplace disability and ill health retirement.

There is also a substantial and diverse market in insurance work in relation to health claims and long term disability products, pension adjudication, workplace rehabilitation, and disability management.

Medicolegal basis

There is a medicolegal basis to much of the work carried out by medical disability analysts whether this be social security law, health and safety legislation, or disability discrimination legislation. Specific training programmes, such as those required by the Department of Social Security before a doctor is approved to perform examinations for state incapacity benefits, cover the legal and procedural context within which doctors are required to provide their advice.

Career structure

Most disability analysts carry out this role in a part time capacity, but about 250 doctors are employed full time in the private sector to provide services under contract to the Department of Social Security and the Benefits Agency. A career in disability analysis may be quite different from one in mainstream clinical practice, but it can provide intellectually stimulating work largely within office hours. Doctors choosing to test the career offered by this specialty will discover that they are trained to enhance their ability to analyse medical evidence, to examine patients to medically sound proto- cols, and to write accurate and succinct reports for decision makers.

Diploma

Disability analysts come from diverse backgrounds, such as general practice, occupational medicine, and rehabilitation medicine. A current priority for the Department of Social Security and private sector providers is the development of a national training curriculum and quality standards for such doctors. A new diploma in disability assessment medicine (DDAM), sponsored by the Faculty of Occupational Medicine of the Royal College of Physicians and the Department of Social Security, is being developed. The diploma will be awarded by examination, encompassing written and clinical sections, and will be open to any doctor with appropriate experience of disability assessment. The syllabus includes the principles and practice of disability assessment, including clinical aspects; assessment of work and the work environment; principles of rehabilitation; and the principles of assurance medicine. The first examination will be held towards the end of 1999.

The diploma will provide formal recognition of disability assessment as a distinct medical specialty with its own body of knowledge and skills. Possession of the diploma will also provide externally validated evidence that an individual has attained a standard of excellence in the specialty. Undoubtedly there will also be greater opportunities for research linked to one of the more established specialties such as general practice or occupational medicine.