Introduction to TBI Model Systems issue.

The six articles contained within this issue are representative of the work of the 2007–2012 Traumatic Brain Injury Model Systems of Care (TBIMS), a programme funded by the US Department of Education, Office of Special Education and Rehabilitative Services, National Institute on Disability and Rehabilitation Research (NIDRR) since 1987. The TBIMS programme has successfully united rehabilitation centres, which provide comprehensive systems of care for individuals with TBI, into a collaborative network conducting research that ultimately improves the lives of individuals with disabilities, their families and their communities. The research activities of each TBIMS centre includes contributing data to a longitudinal database that contains over 10,000 participants, with the longest follow-up cohort being 25 years post-TBI, conducting collaborative research activities within the TBIMS and performing independent research studies that build upon the strengths of the individual institution and the population that it serves. Complete information about the TBIMS programme can be found at the National Data and Statistical Center for the TBIMS website (www.tbindsc.org) which contains extensive information about the TBIMS centres and the Model Systems Knowledge Translation Center website (www.msktc.org) which contains information about the TBI, Spinal Cord Injury and Burn Model Systems of Care. The TBIMS programme has been instrumental in advancing the evidence-base for TBI-related clinical and community-based service delivery. The 2007– 2012 TBIMS grant cycle’s research activities included 24 independent research projects, four modular studies that built upon the TBIMS national database collection effort as well as inter-TBIMS collaboration and two large-scale collaborative projects which were funded separately by NIDRR. The independent research projects primarily employed a randomized clinical trial study design (n1⁄4 18), with two studies using a questionnaire/correlative approach and the remaining five comprised of neuroimaging, quasi-experimental and secondary data analysis approaches. All of the TBIMS were required to participate in at least one modular project. The four that were selected for the 2007– 2012 grant cycle included a prospective study of the relationship between post-TBI fatigue and insomnia, the natural history of headache after TBI, an exploration of sexuality after TBI and a project determining the feasibility of including geographical identifiers (geo-codes) in the TBIMS national database. Finally, the two large-scale collaborative multi-site projects examined the effectiveness of amantadine in managing post-TBI irritability and aggression and a practice-based evidence study of the effectiveness of rehabilitation interventions on outcomes up to 1-year post-TBI. The articles contained within this issue are reflective of the research sophistication of the TBIMS. Four of the studies are single-site studies which investigate complex topics such as: the impact and genesis of post-TBI irritability on spousal and familial relationships (Hammond et al.); the correlation of pre-treatment use of compensatory strategies on activity limitations and cognitive impairment