Table 2: Minimal clinically important difference on the 0–100 mm pain VAS.

StudyPatientsAnchorMCID
TypePointsResponsesDefinitionPoints on anchor scaleUnits on VASa

Pope et al. 2009 [24]RAPGA5Much worsened, somewhat worsened, same, somewhat improved, much improvedDifference between “same” and “somewhat improved or somewhat worsened”±1 point−11.9, +6.8
Tubach et al. 2005 [30]OAPGA5None, poor, fair, good, excellentDifference between “none” and “good” response+3 points−19.9 (knee)
−15.3 (hip)
Hägg et al. 2003 [18]Back painPGA4Worse, unchanged, better, much betterDifference between “unchanged’ and “better” or “worse”±1 point−18, +8
Ehrich et al. 2000 [26]OAPGA5None, poor, fair, good, excellentDifference between “none” and “poor” response on the PGAb+1 point−11.1

MCID; minimal clinically important difference; PGA: patient global assessment of response.
aNegative values indicate improvement, and positive ones indicate deterioration.
bDefined as minimal perceptible clinical improvement.