Swiss national community survey on functioning after spinal cord injury : Protocol, characteristics of participants and determinants of non-response

OBJECTIVE: To detail the protocol, recruitment, study population, response, and data quality of the first population-based community survey of the Swiss Spinal Cord Injury (SwiSCI) Cohort Study. DESIGN: The survey consisted of 3 successive modules administered between September 2011 and March 2013. The first two modules queried demographics, lesion characteristics and key domains of functioning. The third module collected information on psychological personal factors and health behaviour; work integration; or health services and aging. PARTICIPANTS: Community-dwelling persons with chronic spinal cord injury in Switzerland. METHODS: Descriptive analyses of the recruitment process, participant characteristics, and correspondence between self-reported and clinical data. Determinants for participation and the impact of non-response on survey results were assessed. RESULTS: Out of 3,144 eligible persons 1,549 participated in the first two modules (cumulative response rate 49.3%). Approximately three-quarters of participants were male, with a median age of 53 years, and 78% had traumatic spinal cord injury. Record-linkage with medical records demonstrated substantial agreement with self-reported demographic and lesion characteristics. A minimal non-response bias was found. CONCLUSIONS: The community survey was effective in recruiting an unbiased sample, thus providing valuable information to study functioning, health maintenance, and quality of life in the Swiss SCI community