Do Treatment Expectations Moderate the Effect of Manual Therapy in People With Knee Osteoarthritis? A Secondary Analysis of Randomized Clinical Trials

Do a patient's pre-treatment expectations about joint mobilization or massage change how much they benefit from manual therapy for knee osteoarthritis pain?

375 people with knee osteoarthritis, pooled from two randomized — what this means trials

Secondary moderation analysis of two 2x2 factorial RCTs — what this means comparing manual therapy plus exercise against exercise alone, with pain assessed at 9 weeks

• No meaningful interaction between manual therapy and mobilization expectations on 9-week pain (beta -0.17, 95% CI — what this means -0.90 to 0.56)
• No meaningful interaction for massage expectations (beta -0.26, 95% CI — what this means -1.00 to 0.47)
• Expectations were rated pre-randomization on a 5-point scale and split into high vs. low; sensitivity analyses agreed with the main result
• Primary outcome — what this means was Numeric Pain Rating Scale intensity at 9 weeks

In this exploratory analysis, how strongly patients believed in hands-on treatment did not predict who responded better to manual therapy for knee OA pain, so expectation ratings alone appear to have limited value as a treatment-matching signal.