MCID threshold values for PCS, MCS, NDI, and VAS patient-reported outcome scores.

Abbreviations: NDI, Neck Disability Index; VAS, Visual Analog Scale; PCS, Physical Component Summary of the Short Form of the SF-36; MCS, Mental Component Summary of the Short Form of the SF-36; MCID, Minimum Clinically Important Difference; MDC, Minimum Detectable Change; SEM, Standard Error of Measurement. Anchor-based approaches: Mean Change, Change Difference and MDC. They were calculated based on the Health Transition Item of the SF-36 (HTI) as an anchor. Distribution-based approach: SEM.