Overview of the Spinal Cord Injury-Functional Index (SCI-FI): Structure and Recent Advances.

The Spinal Cord Injury-Functional Index (SCI-FI) is a system of patient-reported outcome measures of functional activities developed specifically with and for individuals with spinal cord injury (SCI). The SCI-FI was designed to overcome limitations in measurement of the full range of activities and breadth of content of physical functioning commonly used in SCI research. Generic measurement tools of physical function (ie, those focused on the general population) tend to overemphasize mobility and do not contain enough items at the lower end of the functional range (eg, items appropriate for individuals with tetraplegia). The SCI-FI consists of 9 item response theory-calibrated item banks that represent relevant and meaningful item content for individuals with SCI, span a wide range of functional abilities, and subdivide physical functioning into important subdomains, including basic mobility, self-care, and fine motor function. Since the original publication of the SCI-FI in 2012, there have been significant advances in and publications on the reliability and psychometric properties of the measures. The manuscripts presented in this special section clarify the SCI-FI structure and present new research on the SCI-FI measurement system.