Inception cohort of the Swiss Spinal Cord Injury Cohort Study (SwiSCI): Design, participant characteristics, response rates and non-response.

Objectives To provide a methodological reference paper for the inception cohort of the Swiss Spinal Cord Injury Cohort Study (SwiSCI), by detailing its methodological features and reporting participant characteristics, response rates and non-response bias. Design Prospective cohort study starting in 2013 in all 4 specialized rehabilitation centres in Switzerland. Subjects A total of 655 newly diagnosed patients who received first rehabilitation, aged ≥16 years, with traumatic or non-traumatic spinal cord injury. Methods Descriptive statistics were used to depict participant characteristics and to compare characteristics of responders and non-responders. Logistic regressions were conducted to estimate non-response bias. Results The sample consisted of 70% males, with mean age 53.5 years, 58% had traumatic spinal cord injury, 59.5% paraplegia and 79.3% incomplete spinal cord injury. Males and younger persons more often sustained traumatic spinal cord injury and more severe spinal cord injury, resulting in longer duration of rehabilitation. Complete lesions were more prevalent in traumatic spinal cord injury compared with non-traumatic spinal cord injury. The response rate was 47.5% and study participation was less likely in females, older persons, persons with lower functional independence and those with non-traumatic spinal cord injury. Conclusion SwiSCI inception cohort data enable estimation of epidemiological figures regarding spinal cord injury in Switzerland, and prognostic and trajectory modelling of outcomes after spinal cord injury, which are essential to guide policy, service provision and clinical practice.