The METRIC Study Protocol

Spinal manipulative therapy involves the application of spinal manipulation over several sessions. Spinal manipulation is defined as a high-velocity, low-amplitude thrust performed by a clinician to move a segment of the spine in a specific direction. This type of intervention often generates cavitation sounds (audible pops).

Sham spinal manipulative therapy (sham SMT), was designed to be structurally equivalent to SMT, i.e., to attend to the same body regions with the same amount of contact as well as to have the same number, frequency and length of sessions. SMT and sham SMT will be provided by the same treatment provider and will appear to be similarly tailored to the participants' condition. Sham SMT does not share the component of interest of SMT, i.e., the activation of deep high-threshold mechanoreceptors via high-velocity, low-amplitude thrusts applied to the spine. Yet, it shares all the other components not of interest in this study that may contribute to the placebo response, such as therapeutic alliance, contextual factors, physical touch, and expectations. Furthermore, deception will be used to balance expectations and enhance blinding.

Spinal manipulative therapy involves the application of spinal manipulation over several sessions. Spinal manipulation is defined as a high-velocity, low-amplitude thrust performed by a clinician to move a segment of the spine in a specific direction. This type of intervention often generates cavitation sounds (audible pops).