Table 2.

Mean BPI Worst Pain/Stiffness Score, Pain Interference, and Global Rating of Change

Analysis	No. of Patients	Observed Results								Adjusted Resultsa
		Baselineb		Follow-Up		Within Group		Between Group		Follow-Up		Differencec	95% CI	Pd
		Mean	95% CI	Mean	95% CI	Difference	Pe	Differencef	Pg	Mean	95% CI
BPI worst pain score
Week 6								−0.33	.32			−0.27	−0.88 to 0.34	.38
O3-FAs	108	7.09	6.80 to 7.39	5.41	4.94 to 5.87	−1.69	< .001			5.38	4.77 to 5.99
Placebo	115	6.98	6.71 to 7.25	5.63	5.17 to 6.08	−1.36	< .001			5.65	5.04 to 6.26
Week 12								−0.24	.38			−0.17	−0.79 to 0.44	.58
O3-FAs	102	7.08	6.77 to 7.39	5.34	4.85 to 5.84	−1.74	< .001			5.30	4.68 to 5.91
Placebo	107	6.92	6.65 to 7.20	5.43	4.97 to 5.89	−1.50	< .001			5.47	4.86 to 6.09
Week 24								−0.43	.52			−0.36	−1.08 to 0.38	.34
O3-FAs	94	7.06	6.75 to 7.38	4.83	4.28 to 5.38	−2.23	< .001			4.77	4.04 to 5.50
Placebo	98	6.88	6.59 to 7.16	5.07	4.53 to 5.61	−1.81	< .001			5.13	4.40 to 5.86
BPI pain interference
Week 6								−0.06	.82			−0.05	−0.57 to 0.47	.84
O3-FAs	108	4.14	3.73 to 4.55	3.22	2.74 to 3.69	−0.92	< .001			3.22	2.84 to 3.59
Placebo	115	4.13	3.72 to 4.54	3.27	2.82 to 3.72	−0.86	< .001			3.27	2.91 to 3.63
Week 12								0.10	.74			0.11	−0.44 to 0.66	.70
O3-FAs	102	4.17	3.74 to 4.60	3.14	2.64 to 3.64	−1.03	< .001			3.12	2.73 to 3.51
Placebo	107	4.12	3.70 to 4.55	2.99	2.55 to 3.44	−1.13	< .001			3.01	2.63 to 3.40
Week 24								−0.14	.65			−0.15	−0.39 to 0.70	.58
O3-FAs	94	4.05	3.62 to 4.48	2.57	2.10 to 3.05	−1.48	< .001			2.58	2.19 to 3.00
Placebo	98	4.09	3.64 to 4.54	2.75	2.28 to 3.21	−1.34	< .001			2.74	2.35 to 3.13
Global rating of change in joint pain from baselineh
Week 6								0.10	.56			0.10	−0.24 to 0.44	.57
O3-FAs	109			0.72	0.47 to 0.96	—	< .001			0.72	0.47 to 0.96
Placebo	112			0.62	0.39 to 0.85	—	< .001			0.62	0.38 to 0.86
Week 12								0.27	.16			0.26	−0.10 to 0.63	.16
O3-FAs	98			0.76	0.47 to 1.04	—	< .001			0.75	0.49 to 1.02
Placebo	104			0.49	0.25 to 0.73	—	< .001			0.49	0.24 to 0.75
Week 24								0.08	.74			0.07	−0.35 to 0.49	.74
O3-FAs	90			0.77	0.46 to 1.08	—	< .001			0.77	0.46 to 1.07
Placebo	95			0.69	0.40 to 0.99	—	< .001			0.70	0.40 to 0.99
Global rating of change in joint stiffness from baselineh
Week 6								0.13	.43			0.13	−0.20 to 0.46	.44
O3-FAs	109			0.59	0.35 to 0.82	—	< .001			0.59	0.35 to 0.82
Placebo	114			0.46	0.23 to 0.69	—	< .001			0.46	0.23 to 0.69
Week 12								0.27	.12			0.28	−0.07 to 0.62	.12
O3-FAs	98			0.68	0.41 to 0.95	—	< .001			0.68	0.43 to 0.93
Placebo	103			0.41	0.18 to 0.63	—	< .001			0.41	0.16 to 0.65
Week 24								0.00	1.00			−0.003	−0.41 to 0.41	.99
O3-FAs	91			0.65	0.35 to 0.94	—	< .001			0.65	0.35 to 0.94
Placebo	97			0.65	0.36 to 0.94	—	< .001			0.65	0.36 to 0.94

Abbreviations: BPI, Brief Pain Inventory; O3-FA, omega-3 fatty acid.

^aFrom linear regression adjusting for baseline BPI score and stratification factors.

^bAmong patients with week-6, -12, or -24 BPI worst pain score, respectively.

^cDifference derived from O3-FAs minus placebo.

^dBetween-group P values.

^eP value for paired t tests for difference between baseline and week-12 measures within treatment arm.

^fDifference from change between follow-up and baseline score for O3-FAs minus change between baseline and follow-up for placebo (ie, difference in differences).

^gP value for unpaired t tests for difference in change measures between treatment arms.

^hQuestionnaire evaluates changes in symptoms since last visit, so no baseline scores were collected.