Table 1.

Modified levels of evidence

Evidence level	Description
Level 1	Not applicable given there are no studies with a design that is equivalent to a randomized controlled trial.
Level 2	Longitudinal studies that include a control group (for example, AB group) as they are considered cohort studies where one group is exposed to a particular condition (in this case, a SCI).
Level 3	Longitudinal studies which include historical controls (from chart review or database).
Level 4	Longitudinal studies including at least a baseline and follow-up evaluation (at least equivalent to before-after studies).
Level 5	Cross-sectional studies utilizing both individuals with SCI and AB controls at one point in time.

Abbreviations: AB, able bodied; SCI, spinal cord injury.