Correlations and descriptive statistics.

Chronic pain is a substantial health problem with a high prevalence of comorbid depression. To understand the link between chronic pain and depression, cognitive factors including pain catastrophising and pain self-efficacy have been theorised as significant contributing variables. There is relatively strong evidence that pain catastrophising mediates the relationship between pain severity and depression symptoms. There is also emerging evidence that the mediation role of pain catastrophising may vary as a function of pain self-efficacy. However, it is unknown whether this model will apply in a tertiary pain clinic sample. Thus, this study aimed to examine the respective moderating and mediating roles of pain self-efficacy and pain catastrophising on the association between pain severity and depressive symptoms in a large clinical sample of Australian adults living with chronic pain. Participants (n = 1195) completed all questionnaire measures prior to their first appointments at one tertiary pain service. As expected, the PROCESS path analysis showed that pain catastrophising mediated the relationship between pain severity and depressive symptoms. Further, there was support for the moderating effect of pain self-efficacy; as pain self-efficacy decreased, the relationship strengthened between both pain severity and pain catastrophising, as well as pain catastrophising and depressive symptoms. These findings may have important clinical implications including how relationships between these factors may be considered in the provision of care for those with chronic pain. Notably, these measures could be used in triaging processes to inform treatment decisions.