Fig. 2From: Cross-cultural translation and validation of the Spanish version of the patellofemoral pain and osteoarthritis subscale of the KOOS (KOOS-PF)KOOS-PF mean change scores (negative change represents worsening) vs GROC scores (0 = much worse; 1 = slightly worse; 2 = no change; 3 = slightly better; 4 = much better) demonstrated good correlation (r = 0.64)Back to article page