Bioavailable turmeric extract for knee osteoarthritis: a randomized, non-inferiority trial versus paracetamol

Table 2 Equivalence test of WOMAC scores, CRP, and TNF-α at the end of the study

Parameter	Group (n)	Week 6	Median	Percentile		Mean difference ± SE	Confidence level of mean difference		Equivalence test		Effect size^d
Parameter	Group (n)	Mean ± SE	Median	25th	75th	Mean difference ± SE	90% LCI	90% UCI	Margin of equivalence^d	p value
Total WOMAC^b	Turmeric extract (n = 73)	43.01 ± 2.62	40	26	63	5.08 ± 3.39	− 0.54	10.71	LL = −10.8	0	0.526
Total WOMAC^b	Paracetamol (n = 71)	37.93 ± 2.16	40	21	51	5.08 ± 3.39	− 0.54	10.71	UL = + 10.8	0.0474^$	0.526
Pain^a,b	Turmeric extract (n = 73)	8.78 ± 0.57	8	5	13	0.87 ± 0.75	− 0.38	2.11	LL = −2.2	0.00004	0.486
Pain^a,b	Paracetamol (n = 71)	7.92 ± 0.49	8	5	10	0.87 ± 0.75	− 0.38	2.11	UL = + 2.2	0.0389^$	0.486
Stiffness^b	Turmeric extract (n = 73)	3.01 ± 0.24	3	2	5	− 0.59 ± 0.32	− 1.12	− 0.06	LL = − 1.13	0.0481^$	0.580
Stiffness^b	Paracetamol (n = 71)	3.61 ± 0.21	4	2	5	− 0.59 ± 0.32	− 1.12	− 0.06	UL = + 1.13	0	0.580
Function^b	Turmeric extract (n = 73)	31.22 ± 1.90	30	17.5	45	4.81 ± 2.51	0.65	8.97	LL = − 9.00	0	0.589
Function^b	Paracetamol (n = 71)	26.41 ± 1.64	27	13	40	4.81 ± 2.51	0.65	8.97	UL = + 9.00	0.049^$	0.589
CRP^c	Turmeric extract (n = 72)	14.73 ± 8.12	6	3	6				LL = − 3.00	0.2589^$	0.531
CRP^c	Paracetamol (n = 68)	18.38 ± 2.95	6	4.5	23.5				UL = + 3.00	0	0.531
TNF-α^c	Turmeric extract (n = 69)	17.27 ± 4.08	6	0	12.65				LL = − 6.00	0.0529^$	0.580
TNF-α^c	Paracetamol (n = 68)	48.65 ± 17.17	10	1	28.5				UL = + 6.00	0	0.580

Margin of equivalence or non-inferiority margin = 0.5 of standard deviation. Effect size = margin of equivalence/standard deviation
LCI lower confidence interval of mean difference, UCI upper confidence interval of mean difference, LL lower limit of margin of equivalence, UL upper limit of margin of equivalence, SE standard error
^aWOMAC pain scale is the primary outcome measure
^bAspin–Welch unequal–variance T test for equivalence using two one-sided test (TOST)
^cMann–Whitney U or Wilcoxon rank-sum location difference test for equivalence using two one-sided test (TOST)
^dSee Additional file 3 for the derivation of margin of equivalence and effect size
^$Higher p value is considered

ISSN: 1745-6215