NeuroRehabilitation 34 (2014) 781–788 DOI:10.3233/NRE-141084 IOS Press 781 Multilevel modeling of partnered relationship trajectories and relationship stability at 1, 2, and 5 years after traumatic brain injury in Norway Marit V. Forslund a,b , Juan C. Arango-Lasprilla d , Cecilie Roe a,b , Paul B. Perrin e and Nada Andelic a,c,* a Department of Physical Medicine and Rehabilitation, Oslo University Hospital, Oslo, Norway b Faculty of Medicine, University of Oslo, Oslo, Norway c Institute of Health and Society, CHARM (Research Centre for Habilitation and Rehabilitation Models and Services), Faculty of Medicine, University of Oslo, Oslo, Norway d IKERBASQUE, Basque Foundation for Science, University of Deusto, Bilbao, Spain e Virginia Commonwealth University, Richmond, VA, USA Abstract. OBJECTIVES: The aims of this study were to examine (a) predictors of partnered relationship probability trajectories and relationship stability across 1, 2, and 5 years after traumatic brain injury, and (b) influences on the slopes of these trajectories. MATERIALS AND METHODS: Individuals (n = 105) from Norway with acute TBI were assessed during admission to an urban trauma center and again at 1, 2 and 5 years after injury. The outcome measures were partnered relationship status (partnered vs. single) at 1, 2 and 5 years post-injury investigated through multilevel modelling, and relationship stability (stable, unstable, and single) investigated through multinomial logistic regression. Independent variables were sex, age at injury, partnered relationship at injury, having dependent children, education, employment and occupation status at time of injury, acute Glasgow Coma Scale score, posttraumatic amnesia, and length of stay in hospital. RESULTS: Partnered relationship status at injury and the interaction of relationship status at injury by time, employment at injury and the interaction of TBI severity by time were significant predictors of participants’ relationship trajectories. Having dependent children at the time of injury, higher education, and being in a blue collar occupation at time of injury were significant predictors of relationship stability. CONCLUSIONS: The identification of these influences on partnered relationship probability trajectories and stability could help clinicians and researchers develop and refine early interventions to reduce relationship dissolution in the first several years after brain injury. 1. Introduction Traumatic brain injury (TBI) is a worldwide pub- lic health problem and a leading cause of death and * Address for correspondence: Nada Andelic, Oslo University Hospital, Department of Physical Medicine and Rehabilitation, Post- boks 4950 Nydalen, 0424 Oslo, Norway. Tel.: +47 22118687; Fax: +47 22115022; E-mail: nandelic@online.no. disability among young adults. TBI can cause chronic or life-long physical, cognitive, behavioral and emo- tional impairments, with challenges in employment, community integration, social life and family and part- ner relationships. However, these effects extend beyond just the per- son with TBI. As compared with healthy controls, the romantic partners of individuals with TBI report higher 1053-8135/14/$27.50 © 2014 – IOS Press and the authors. All rights reserved