Table 2 Examples of search terms for key concepts

Chronic low back pain

“back pain”, “low back pain”, LBP, “chronic low back pain”, cLBP, “non?specific low back pain”, “non?specific back pain”, “lumbar pain”

Placebo effects/Contextual Factors

(placebo ADJ (effect* OR response* OR analgesi*)), (nocebo ADJ (effect* OR response*), (context* ADJ (factor* OR effect* OR response*)), (common ADJ (factor* OR effect*)), (non?specific ADJ (effect* OR factor*))

Healthcare professionals and patient relationships/interactions

alliance*, (patient ADJ (relation* OR interact*)), (empath* OR warm* OR compassion* OR kind* OR friendl*), rapport, “non?verbal communication*”, “verbal communication*”, “health communication*”, "initial consultation", "professional-patient relation*","physician-patient relation*"

Healthcare professionals and patient expectations/beliefs

(patient* ADJ (expect* OR belief* OR attitude*)), (practitioner* ADJ (expect* OR belief* OR attitude*)), (positive ADJ (expect* OR suggest*)), (negative ADJ (expect* OR suggest*)), illness ADJ (perception* OR belief*)