Low back pain (LBP) is one of the most disabling conditions and has major socio-economic consequences. The prevalence of LBP among the population worldwide ranges between 15 and 45%. In the Kingdom of Saudi Arabia (KSA), the prevalence of LBP reported being around 18.8% among the population. Patient beliefs about back pain, pain self-efficacy, pain catastrophizing and expectation all seem to play a role in recovery. In fact, clinical guidelines recommended the treatment of non-specific chronic LBP should be considered within a multi-factorial biopsychosocial (BPS) framework. Exactly how this treatment should be delivered is not clear.

Pain neuroscience education (PNE) is a cognitive-based education that helps to educate patients about pain by focusing on neurobiology, neurophysiology and the processing and representation of pain. Even though PNE as intervention helps to improve pain, disability and other patient outcome, mixed results on its efficacy have seen in many studies. Since any complicated interventions are usually assessed by their effects on outcomes such as disability and pain, most do not target these outcomes directly; instead, they target mediating factors that are assumed to cause changes in these outcomes. In particular self-efficacy, pain catastrophizing and a patient's beliefs about back pain are thought to mediate the PNE-disability relationship since most of these cognitive factors are either highly correlated with disability or predictors for disability. The justifications for choosing these potential mediating factors: (1) self-efficacy has been shown to mediate the development of disability and is the most commonly identified mediator for psychological and behavior change interventions; (2) a study has shown that higher levels of pain catastrophizing are strongly correlated with higher levels of pain intensity and disability; and (3) a study has shown that beliefs about the consequences of LBP can influence patients' perceived pain and disability. However, the mechanisms underlying PNE effects, or the effect of PNE on mediating factors and its subsequent effect on disability as an outcome, has not been yet investigated. That leads to a knowledge gap in the evidence for understanding how PNE exerts its effect on disability. Also, identifying potential moderating factors that influence the PNE-disability relationship needs further investigation. In particular, expectation is thought to moderate the PNE-disability relationship because there are studies identified a link between expectation and clinical outcomes in patients with LBP. No study has explored the relationship between expectancy and clinical outcomes in the context of PNE. So, the influence of patient expectation on the magnitude of PNE effect on disability needs investigation.

The purpose of this 18-months project is understanding the underlying mechanisms of how PNE impacts disability. This project is significant because it will help us understand how PNE works by studying the underlying mechanisms and for whom and under what circumstances will PNE produces the greatest clinical benefits on the disability for patients with chronic LBP. Knowing how certain factors work will help PTs to enhance the elements of PNE that hopefully will target patient-specific factors and subsequently will reduce disability.