OUTCOMES THAT MAnER

COSSTKCC I'IOS and validation o f practice guidelines and clinical pathways are receivlng increasing attention in all areas of health care. As practice guidelines proliferate, it is being urged that they be based on peer-reviewed, scientific evidence, not simply on the encoding of usual practice based o n expert opinion. In the field of developmental disabil- ities, two other critical aspects must be taken into account: the need for a conceptual franiework or classification system within which to gather and interpret research data and compare treatments, and a consensus about which outcomes should be measured.

Current and new methods of treatment should be evaluated for effects o n rnultiple levels of the disabling process. 'The National Center for Medical Rehabilitation Research ( K C M R R ) has developed a framework to evaluate effects of the outcomes of niethods of treatment at multiplc levels'. This model combines aspectes of the wffo classification system of i t t i p i i r t w t i t . s , di.sciDi1itie.s and hatidicuiw2. with a niodel developed by Nagi '. The Nagi model includes a category of fuucriotilil lit,iitatioti.s i t i total body ticti\*itics which addresses an important aspect of intervention by therapists. The KChlKR classifica- tion system allows us to track both primary and secondary effects of the disability on the bodily functions of people with disabling conditions. as well as their ability to perform appropriate social roles. The first four lcvels are pertinent t o the evaluation of health- care interventions: 1 ) pathophysiology or effects at the cellular/nmlecular level: (2) impairments or effects at the orgadorgan system level; (3 ) functional limitations or effects at the total body/body segment level; and (4) disability or effects at the level of typical role fulfillrnent at home, school, work and in community life. The fifth dimension of the KcMKK system is societal limitations. These are barriers to ful l participation in society due to attitudes. architectural barriers and social policies.

Without such a system, review of the literature yields a mixture of information from a variety of specialty areas, e.g. pharmacology; orthopedics, neurology, rehabilitation medicine and education. There is little consistency in what has been measured and how i t was measured, making it difficult to assess the efficacy of, and to compare, treatments. With cerebral palsy. for example, physiologically-concerned specialists have focused on spasticity: therapeutically-concerned specialists have investigated techniques t o improve gait, speech and hand use; and developmentally-concerned specialists have been con- cerned with the ability to perform tasks and assistance necessary, and social interactions. Most of the outcome measurements in the literature have been made at the pathophysio- logical and impairnient levels, with the untested assumption that improvement at these levels will automatically translate to improvement at the functional and disability levels.

An effective classification system allows us to understand the evidence we already have and t o know what additional evidence may be required to determine the efticacy of

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treatments. Most existing studies report outcomes ilt o n l y one of these levels. but with this classification system, we can construct evidence tables on a matrix of these four dimensions and compile information from across studies. For example. studies of selec- tive posterior rhimtomy can be reviewed, with outcomes recorded i n the appropriate cells of the matrix. This can demonstrate what evidence exists on the effects o f this surgery ;it the pathophysiological level, the impairment level, the functional limitation level and the disability level. Such a rnatrix ciln readily demonstrate at which levels adc- quate information is lacking. In designing new investigations with outcome measures at each of these levels, we can trace the effects of ;in intervention at the pathophysiologicit1 level, for example. across t o the impairment, functional limitation and disability levels.

The second aspect of outcome nicasurenient that must be addressed is concerned with the lack of consensus about which outcomes are desirable-and by whom. Outcome nieiisures to date have been determined almost exclusively by health-care professionals. But who lives with the treatments and faces the reality o f the outcomes? Our patients. We must listen to our patients to determine the kinds of outcomes that are important t o improve the quality of their lives. Groups such as the NARK Advisory Board have made i t clear that people with disabilities are primarily concerned with outcomes at the levels o f functional limitation, disability and societal limitation, because i t is i n these dimen- sions that they experience their medical condition. Many would argue that the provision of a powered wheelchair that allows freedom of mohility (treatment at the functional limitation level) is preferable to any one of ;I variety o f treatments intended t o decrease spasticity (treatment at the impairment level), even if i t were known to improve the ability to walk. The cost, from the patient's perspective. may be too high in tcr~iis 01' interim-restricted mobility. dollars and pain. and in ternis o f the comiiiitnicnt to intensive physical therapy and orthotic use follmving surgery compared with the qualitative o r quantitative improvement that may be attained by ivillking.

Disability treatment/research requires a conceptual framework or classification system tor considering treatment outcomes. With such a tool we can begin to reach a consensus about what we do and and do not yet know about individuul treatments, about what each offers (i .e. at what level i t has effects), and to put treatments into perspective with one another. As we attempt t o assess the success or failure of our treattnciits, we must dcter- mine which outcoiiies are desirable. People with disabilities and their parents, teachers and various health-care providers niay have differing views about this. I suggest that efficacy ultimately must be determined by those who live with the trcatriients and face the reality of the outcomes: o u r patients. We must listen to the views o f groups of adult people living with disabilities. as well as individuals seeking advice about treatment.

Why must we construct evidenc&ised guidelines iicross multiple levels of the dis- abling process and why must we listen to o u r patients? S(J that consumers can make inforrned choices that are consistent with their own values and circumstances. So that the behavior of health-care providers is guided by the best evidence we have. S o that we can convince recalcitrant tunders that what we recommend is worth doing. So that we know what questions fu ture research needs t o answer. So that we can know that we are serving our patients and society to the best o f our abilities.

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