Table 2. Primary, Prespecified Secondary, and Post Hoc Outcomes for Patients for Whom Outcome Data Were Available at 6 Months and/or 18 Months.

Outcome measures	Diet and exercise				Attention control				Adjusted mean difference (95% CI)	P valuea
	Baseline (SD)	18 Months			Baseline (SD)	18 Months
		Adjusted mean (95% CI)	Unadjusted mean (SD)	Absolute change (95% CI)		Adjusted mean (95% CI)	Unadjusted mean (SD)	Absolute change (95% CI)
Primary outcome
WOMAC pain scoreb	7.4 (3.1) [n = 377]	5.0 (4.6-5.4) [n = 329]	5.0 (3.8) [n = 329]	−2.4 (−2.8 to −2.1)	7.4 (3.1) [n = 316]	5.5 (5.1-5.9) [n = 316]	5.5 (3.7) [n = 316]	−1.8 (−2.2 to −1.4)	−0.6 (−1.0 to −0.1)	.02
Secondary outcomes
Body weight, kg	99.6 (19.3) [n = 377]	91.4 (90.2-92.6) [n = 289]	89.8 (17.2) [n = 289]	−7.7 (−8.7 to −6.7)	100.8 (22.2) [n = 343]	97.4 (96.2-98.7) [n = 273]	98.4 (21.7) [n = 273]	−1.7 (−2.5 to −0.8)	−6.0 (−7.3 to −4.7)	<.001
Waist circumference, cmc	113 (14) [n = 376]	105 (104-107) [n = 212]	104 (14) [n = 212]	−9 (−10 to −8)	115 (16) [n = 342]	111 (109-113) [n = 214]	111 (16) [n = 214]	−4 (−5 to −3)	−5 (−7 to −4)	<.001
WOMAC function scored	25.5 (11.5) [n = 377]	16.5 (15.3-17.7) [n = 325]	16.6 (13.1) [n = 325]	−9.2 (−10.5 to −7.9)	25.5 (11.4) [n = 343]	19.8 (18.6-21.0) [n = 311]	19.5 (12.6) [n = 311]	−5.5 (−6.9 to −4.1)	−3.3 (−4.9 to −1.7)	<.001
Six-minute walk distance, me	373 (90) [n = 375]	419 (411-428) [n = 247]	427 (103) [n = 247]	41 (32 to 51)	371 (95) [n = 341]	376 (368-385) [n = 219]	375 (97) [n = 219]	−4 (−12 to 4)	43 (31 to 55)	<.001
Pain medication use	8.2 (5.0) [n = 377]	8.3 (7.9-8.8) [n = 231]	8.3 (5.0) [n = 231]	−0.1 (−0.5 to 0.3)	8.4 (5.0) [n = 343]	8.3 (7.8-8.8) [n = 228]	8.3 (5.0) [n = 228]	−0.4 (−0.8 to 0.0)	0.0 (−0.5 to 0.5)	.90
Short Form 36 score (range, 0-100)f
Physical subscale	34.3 (9.2) [n = 377]	41.4 (40.2-42.6) [n = 321]	41.2 (11.1) [n = 321]	6.7 (5.6 to 7.7)	35.9 (9.1) [n = 343]	37.6 (36.3-38.8) [n = 306]	38.4 (10.6) [n = 306]	2.1 (1.2 to 3.1)	3.8 (2.5 to 5.2)	<.001
Mental subscale	55.4 (9.8) [n = 377]	55.3 (54.3-56.2) [n = 321]	55.2 (9.1) [n = 321]	0.1 (−0.9 to 1.1)	55.0 (9.7) [n = 343]	54.1 (53.1-55.0) [n = 306]	54.0 (11.3) [n = 306]	−1.0 (−2.4 to −0.4)	1.2 (−0.1 to 2.5)	.07
Post hoc outcomes
PASE scoreg	116 (60) [n = 375]	139 (133-146) [n = 311]	138 (69) [n = 311]	23 (15 to 30)	112 (58) [n = 339]	117 (111-124) [n = 284]	114 (53) [n = 284]	1 (−6 to 8)	22 (13 to 31)	<.001
CES-D scoreh	5.2 (4.8) [n = 374]	3.9 (3.2-4.7) [n = 243]	3.8 (4.2) [n = 243]	−1.1 (−1.7 to −0.6)	5.5 (5.2) [n = 341]	4.6 (3.9-5.3) [n = 226]	5.0 (5.7) [n = 226]	−0.4 (−1.0 to 0.3)	−0.6 (−1.3 to 0.0)	.07

Abbreviations: CES-D, Center for Epidemiologic Studies Depression Scale; MCID, minimum clinically important difference; MCII, minimum clinically important improvement; PASE, Physical Activity Scale for the Elderly; WOMAC, Western Ontario and McMaster Universities Osteoarthritic Index.

^a All model-adjusted estimates were created from a mixed linear model fit with treatment group, visit number, and treatment-by-visit interaction, adjusted for baseline body mass index, clinic site, sex, and baseline values of the outcome. Contrast statements were used to produce visit-specific means, mean differences, and P values.

^b Range, 0 to 20 (0, no pain; 2 to 8, mild; >8 to 14, moderate; and >14 to 20, severe); between-group MCID = 1.6, calculated as half the SD.³⁷

^c Waist circumference thresholds (women, >88 cm; men, >102 cm) for increased health risk.²⁹ MCID = −7.5 cm.^24,37

^d Range, 0 to 68 (higher scores indicate poorer function); between-group MCID = 6.²⁵

^e The maximum distance a participant could walk along a standardized walkway in 6 minutes. Within-group MCII, 26 m to 55 m.²⁶

^f Health-related quality-of-life physical and mental health summary scores; range, 0 (worst) to 100 (best); within-group MCII = 5 for both physical and mental subscales.²⁸

^g Score range, 0 to 400 (higher scores indicate more activity; MCII = 17-25).³⁹

^h Score range, 0 to 30 (score of ≥10 indicates presence of significant depressive symptoms); MCID = 30, calculated as half the SD.³⁶