Self-efﬁcacy is more important than fear of movement in mediating the relationship between pain and disability in chronic low back pain Luciola da C. Menezes Costa a, * , Christopher G. Maher a , James H. McAuley a , Mark J. Hancock b , Rob J.E.M. Smeets c,d a Musculoskeletal Division, The George Institute for International Health, The University of Sydney, Australia b Back Pain Research Group, Faculty of Health Sciences, University of Sydney, Australia c Adelante Centre of Expertise in Rehabilitation and Audiology, Hoensbroek, The Netherlands d Department of Rehabilitation Medicine, Caphri, Maastricht University, The Netherlands article info Article history: Received 8 April 2010 Received in revised form 10 June 2010 Accepted 17 June 2010 Available online 23 July 2010 Keywords: Self-efﬁcacy Fear of movement Mediation analysis Low back pain abstract Pain self-efﬁcacy and fear of movement have been proposed to explain how pain can lead to disability for patients with chronic low back pain. However the extent to which pain self-efﬁcacy and fear of move- ment mediate the relationship between pain and disability over time has not been investigated. This study aimed to investigate whether pain self-efﬁcacy and/or fear of movement mediate the relationship between pain intensity and disability in patients with recent onset chronic low back pain. In a two-wave longitudinal design, 184 chronic low back pain patients completed measures for pain intensity, disability, pain self-efﬁcacy and fear of movement at baseline and 12 months after the onset of chronic low back pain. Regression analyses were used to test the mediational hypothesis. We found that, when measured at the same time, both pain self-efﬁcacy and fear of movement beliefs partially mediated the effects of pain intensity on disability at the onset of chronic low back pain. However, in the longitudinal analyses, only improvements in self-efﬁcacy beliefs partially mediated the relationship between changes in pain and changes in disability over a 12 months period. We found no support for the theory that fear of move- ment beliefs mediate this relationship. Therefore, we concluded that pain self-efﬁcacy may be a more important variable than fear of movement beliefs in terms of understanding the relationship between pain and disability. Ó 2010 European Federation of International Association for the Study of Pain Chapters. Published by Elsevier Ltd. All rights reserved. 1. Introduction Many patients who have persisting low back pain have difﬁ- culty performing their usual activities. There is considerable indi- vidual variation in the extent of low back disability and despite considerable attention researchers have had only limited success in identifying the factors that might be responsible for this. Sup- port for the role of psychological factors in explaining the develop- ment and maintenance of chronic low back pain and disability has grown due largely to their ability to inﬂuence the problem of pain and many of the related symptoms. One of the ways in which these factors have been proposed to explain the relationship between pain and disability is by mediation (Vlaeyen et al., 2005). A mediational hypothesis aims to identify the mechanism that underlines an observed relationship between two variables (MacKinnon et al., 2000). This is achieved by including a third variable in the model, known as a mediator variable, whose inﬂu- ence explains how the two variables are related. The mediator var- iable therefore provides critical information regarding the identiﬁcation of potential targets for interventions. In the low back pain literature two factors that are frequently proposed to mediate the relationship between pain intensity and disability are pain self- efﬁcacy and fear of movement. Based on the theory of social learning, self-efﬁcacy describes the conﬁdence the person has in his or her own ability to achieve a desired outcome (Bandura, 1977). Higher levels of self-efﬁcacy have been found to be associated with lower levels of pain and disability in patients with chronic pain (Reid et al., 2003; Denison et al., 2004; Dohnke et al., 2005). Nicholas et al. (1992) and Altmaier et al. (1993) also demonstrated that pain-related self-efﬁcacy ratings are likely to change following cognitive behavioural management of low back pain and that these changes were associated with better outcomes such as reduced disability. The fear avoidance model was proposed to explain why patients who are experiencing noxious or threatening stimuli reduce their 1090-3801/$36.00 Ó 2010 European Federation of International Association for the Study of Pain Chapters. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.ejpain.2010.06.014 * Corresponding author. Address: PO Box M201, Missenden Road, NSW 2050, Australia. Tel.: +61 2 9657 0396; fax: +61 2 9657 0302. E-mail address: lmenezes@george.org.au (L. da C.M. Costa). European Journal of Pain 15 (2011) 213–219 Contents lists available at ScienceDirect European Journal of Pain journal homepage: www.EuropeanJournalPain.com