Outcome measures: evolution in clinical trials of neurological/functional recovery in spinal cord injury

The need to determine the beneficial effect of the treatment of spinal cord injury (SCI) requires clearly defined standardized measures of the severity of injury and how well the function is restored. Improved neurological recovery should be linked to increased capacity to perform tasks such as walking, reaching and grasping, which results in meaningful gains in mobility and self-care. Measurements of recovery, capacity, mobility and self-care are the outcomes used to determine the benefits from the treatment and have evolved over the last century with contributions by the mentors and protégés of Sir Ludwig Guttmann, whom we honor today. Randomized clinical trials in the past 20 years have taught us many lessons as to which outcome measures have the greatest validity and reliability. The International Standards for Neurological Classification of SCI have become the clinical gold standard for measurement of severity, but would benefit from pathophysiological surrogates to better understand the mechanisms of recovery. Measurements of walking capacity have emerged as valid/reliable/responsive and upper extremity measures are in development, which help distinguish neurological improvement from rehabilitation adaptation. Performance of self-care and mobility has been linked to capacity and severity outcomes. In addition, new partnerships between clinical trial entities, professional societies, industry and federal agencies should facilitate identification of priorities and uniformity of measurement standards. Our ultimate goal is to improve the quality of life of those individuals with SCI whom we serve, but we must focus our investigative efforts carefully, systematically and rigorously as clinical scientists.