Table 2 Mean difference within-groups at 2, 6 and 12 months follow up (available case analysis by GEE)

From: The comparison effects of intra-articular injection of Platelet Rich Plasma (PRP), Plasma Rich in Growth Factor (PRGF), Hyaluronic Acid (HA), and ozone in knee osteoarthritis; a one year randomized clinical trial

  Test of Within-group effect) mean change from baseline) Between-group
PRP(n = 52) PRGF (n = 51) HA(n = 49) Ozone (n = 48)   
Outcomes MDa(95%CI) MDa(95%CI) MDa(95%CI) MDa(95% CI) P value# P value##
WOMAC
Pain T2 −4.8 (−5.2,-4.3)*** −4.8(− 5.4,-4.2)*** − 4.3(− 4.6,-3.9)*** −5.9(−6.4,-5.5)*** < 0.001 < 0.001
 T6 − 4.8(− 5.2,-4.3)*** −4.8(− 5.4,-4.2)*** −3.8(− 4.1,-3.4)*** −3.1(− 3.5,-2.6)*** < 0.001 0.003
 T12 −4.4(− 4.9,-4.0)*** −4.4(− 4.9,-3.8)*** −3.1(− 3.5,-2.8)*** − 1.7(− 2.2,− 1.3)*** < 0.001 < 0.001
 FRACTIONb 45.52% (40.1,50.9) 45.37 (39.1,51.6) 33.68% (29.4,37.9) 21.72 (17.5,25.8)   
Stiff T2 − 1.3(− 1.6,-1.0)*** -1.3(− 1.6,-0.88)*** −1.5(− 1.8,-1.3)*** −1.2(− 1.4,-1.0)*** 0.93 0.23
T6 −1.5(− 1.8,-1.2)*** −1.5(− 1.8,-1.0)*** −1.5(− 1.7,-1.3)*** −0.8(− 1.0,-0.5)*** 0.002 0.16
T12 − 1.0(− 1.3,-0.7)*** −0.96(− 1.3,-0.6)*** −0.8(− 1.1,-0.6)*** −0.2(− 0.4,0.03)*** < 0.001 0.09
FRACTIONb 40.09% (29.7,50.4) 38.15% (29.1,47.2) 38.71% (29.9,47.4) 30.86% (19.7,41.9)   
Fun T2 − 11.1(− 12.6,-9.6)*** − 11.4(− 13.2,-9.7)*** −11.5(− 12.8,-10.2)*** −15.9(− 17.0,-14.8)*** 0.008 0.002
T6 −12.6(− 14.1,-11.1)*** − 13.1(− 14.-11.4)*** −10.8(− 12.1,-9.4)*** −8.0(− 9.1,-6.8)*** < 0.001 < 0.001
T12 − 10.0(− 11.0,-8.8)*** − 10.5(− 12.2,-8.8)*** −5.8(− 7.1,− 4.4)*** -4.4(− 5.5,-3.3) < 0.001 < 0.001
FRACTIONb 33.99% (28.5,39.4) 37.41% (31.9,42.9) 21.22% (17.2,25.2) 14.99% (11.8,18.1)   
Total T2 −17.2(− 19.1,-15.3)*** − 17.5(− 19.9,-15.3)*** −16.4(− 18.1,-14.6)*** −23.1(− 24.5,-21.7)*** < 0.001 < 0.001
T6 −19.0(− 20.9,-17.1)*** − 19.4(− 21.7,-17.1)*** − 14.7(− 16.4,-12.9)*** −11.9(− 13.2,-10.5)*** < 0.001 0.001
T12 −15.5(− 17.4,-13.6)*** −15.9(− 18.2,-13.6)*** −8.4(− 10.1,-6.7)*** −6.4(− 7.7,-5.0)*** < 0.001 < 0.001
FRACTIONb 36.50% (31.2,41.7) 38.5% (32.9,44.09) 23.08% (19.8,26.4) 15.5% (12.4,18.6)   
LEQ
Pain T2 − 1.3(− 1.7,-1.0)*** − 1.3(− 1.6,-0.9)*** −1.9(− 2.2,-1.6)*** − 2.5(− 2.8,-2.2)*** < 0.001 < 0.001
 T6 − 1.7(− 2.1,-1.4)*** − 1.7(− 2.0,-1.3)*** −1.6(− 1.9,− 1.3)*** -1.3(− 1.6,-1.10)*** 0.089 0.08
 T12 −1.4(− 1.8,-1.1)*** −1.3(− 1.7,− 1.0)*** -1.0(− 1.3,-0.7)*** − 0.5(− 0.7,-0.2)*** < 0.001 < 0.001
 FRACTIONb 27.37% (21.4,33.3) 27.96% (21.7,34.2) 25.77% (20.3,31.2) 16.11% (11.9,20.2)   
Walk T2 − 0.46(− 0.6,-0.3)*** − 0.4(− 0.6,-0.2)*** −0.5(− 0.7,− 0.3)*** −0.3(− 0.4,-0.2)*** 0.34 0.97
T6 −0.3(− 0.5,-0.2)*** -0.3(− 0.5,-0.2)*** −0.4(− 0.5,-0.2)*** −0.14(− 0.3,-0.02)* 0.14 0.88
T12 −0.25(− 0.4,-0.07)** −0.2(− 0.3,0.01) −0.16(− 0.3,0.01) −0.06(− 0.2,0.06) 0.13 0.84
FRACTIONb 39.42% (28.6,50.2) 30.38% (19.5,41.2) 21.06% (11.4,30.7) 13.76% (4.8,22,7)   
ADL T2 − 1.3(− 1.6,-1.0)*** − 1.2(− 1.5,-0.9)*** −1.3(− 1.5,-1.2)*** −1.3(− 1.5,-1.2)*** 0.077 0.19
T6 −1.7(− 2.0,-1.4)*** − 1.7(− 1.9,-1.4)*** −0.9(− 1.1,-0.7)*** −0.9(− 1.1,-0.7)*** < 0.001 < 0.001
T12 −1.1(− 1.4,-0.8)*** −1.1(− 1.3,-0.8)*** −0.4(− 0.6,-0.3)*** −0.4(− 0.6,-0.3)*** < 0.001 < 0.001
FRACTIONb 21.7% (17.2,26.2) 22.2% (17.7,26.7) 10.89% (8.5,13.3) 7.07% (5.3,8.8)   
Total T2 − 3.2(− 3.7,-2.6)*** − 3.0(− 3.7,-2.4)*** − 3.4(− 3.8,-2.9)*** − 4.5(− 4.8,-4.1)*** < 0.001 0.021
T6 − 3.8(− 4.4,-3.2)*** −3.7(− 4.4,-3.1)*** − 2.4(− 2.9,-1.9)*** −2.2(− 2.5,-1.8)*** < 0.001 0.006
T12 −2.8(− 3.4,-2.3)*** −2.6(− 3.2,-1.9)*** − 1.2(− 1.6,-0.7)*** − 0.9(− 1.2,-0.5)*** < 0.001 < 0.001
FRACTIONb 23.52% (19.0,28.0) 22.58% (17.7,27.4) 13.37% (10.3,16.5) 11.03% (8.6,13.4)   
VAS (1–10)
 T2 −5.2(− 5.6,-4.8)*** −5.2(− 5.6,-4.8)*** −5.3(− 5.6,-4.9)*** −5.9(− 6.3,-5.6)*** 0.008 0.022
 T6 −4.6(− 4.9,-4.2)*** −4.5(− 4.9,-4.1)*** −4.2(− 4.6,-3.9)*** −4.0(− 4.3,-3.7)*** 0.02 0.013
 T12 −3.3(− 3.7,-2.9)*** −3.4(− 3.7,-3.0)*** −2.6(− 2.9,-2.3)*** −1.3(− 1.6,-1.0)*** < 0.001 < 0.001
 FRACTIONb 42.37% (37.2,47.5) 42.38% (37.3,47.5) 31.59% (27.6,22.1) 18.69% (15.2,22.1)   
  1. MD, mean difference; CI, confidences interval; T2, 2nd month post injection; T6, 6th month post injection; T12, 12th month post injection;
  2. a 2nd month−baseline; b(|Baseline− 12th month|/Baseline)*100; *Within-group effects p < 0.05; **Within-group effects p < 0.01; **Within-group effects p < 0.001
  3. # Adjusted generalized estimating equations model after controlling the baseline Outcome, sex, age, BMI;
  4. ## crude repeated measures AVOVA