Rehab Research Principles & Terms
Scientifically, to “rehabilitate” implies to engage in a rehabilitative process yielding improvement in function that is beyond any spontaneous recovery, for example in limb function, speech, balance, social behavior. While targeting the whole person, the focus of rehabilitation science and engineering, as developed in the Institute of Medicine’s seminal consensus book entitled Enabling America – Rehabilitation Science and Engineering, is on a multidisciplinary understanding of the enabling-disabling process. The underlying motivation is a fundamental principle: that tissues and systems of cells – ranging from connective soft tissue to muscle to neurocircuitry to bone – can “remodel” as long as there is access to an adequate internal support infrastructure (e.g., blood supply), and the involved structures are “used” appropriately. The latter represents a great scientific challenge, given the complexity of the human system and its adaptive processes. From this perspective, the objective of the clinical rehabilitative process is to employ an optimum intervention strategy that will maximize desired outcomes (e.g., maximum function and social re-integration per unit cost). Clearly rehab bioengineers have much to contribute.
But engineers also must recognize that most rehab research is not founded in sensor-based measurements of the type that engineers are used to. For better or worse, the foundation for most clinical rehabilitation research is the use of ordinal scores (e.g., 0-3, 1-5) that are completed by a trained observer (e.g., research therapist) or self-reporting. There are many such assessment "instruments" for many different purposes within rehab (e.g., common for stroke: NIH Stroke Score; Fugl-Meyer; Functional Independence Measure), and you will hear of a number of those throughout the course. One of the challenges is that most rehab interventions are not based "randomized clinical trials" (RTC's), which are considered the gold standard for "evidence-based practice."
You should know the following clinical research assessment terms that are commonly used in relation to the use of scoring instruments:
validity: Extent to which a measure actually measures what it is intended to, i.e. the degree to which evidence supports the inferences that are made from a score. Types include
· content (are all relevant concepts or items within the domain of interest represented?),
· criterion (is it consistent with “gold standard”?),
· predictive (does it predict important events in the future, e.g. clinical outcome?),
· concurrent (does it correlate with events occurring at the time, or other scales?);
· ecological (is it meaningful or useful in the person’s real life, outside of the clinical setting?).
reliability: The extent to which a score or measure is free of random error or noise, i.e. the degree to which an instrument is consistent, reproducible (e.g., test-retest), and repeatable when administered by appropriately trained individuals
bias: Systematic error in a measure, usually associated with subjective self-reporting or stakeholder-reporting, or attitudinal measures.
sensitivity: Ability of measure(s) to detect true cases, to discriminate between meaningful differences, and to indicate changes in the true attribute being measured.
Copyright by Jack Winters.