Table 2.

Primary Outcomes Over Time^a

	Outcome
Treatment Group		Low Back Pain Intensity			Back-Related Disability			Pain Impact
Treatment Group	n	Mean	95% CI	P	Mean	95% CI	P	Mean	95% CI	P
Overall Analysis
Control	201	5.92	5.68-6.17	0.46	14.81	13.99-15.62	0.36	31.22	30.00-32.43	0.13
LTOT	201	6.06	5.80-6.32	0.46	15.32	14.55-16.09	0.36	32.51	31.33-33.70	0.13
Analysis for Continuous Duration of LTOT
Control	201	5.92	5.68-6.17	0.56	14.81	14.00-15.62	0.88	31.22	30.00-32.43	0.43
LTOT (months)
3	43	5.82	5.18-6.45		15.68	14.00-17.37		31.38	28.49-34.28
6	23	6.40	5.53-7.28		15.69	13.32-18.06		33.55	30.12-36.99
9	16	5.60	4.75-6.45		15.17	11.98-18.36		31.48	26.74-36.22
12	119	6.13	5.82-6.45		15.16	14.19-16.12		32.83	31.39-34.26
Analysis for Opioid Dose Response Based on Number of Quarters Used
Control	201	5.92	5.68-6.17	0.73	14.81	14.00-15.62	0.81	31.22	30.00-32.43	0.50
LTOT (quarters)
1	25	5.64	4.75-6.53		15.60	13.72-17.49		30.97	27.83-34.11
2	23	6.27	5.32-7.21		14.94	12.26-17.62		32.95	28.59-37.31
3	34	5.91	5.31-6.50		15.99	14.00-17.99		32.09	29.04-35.15
4	119	6.13	5.81-6.45		15.16	14.19-16.12		32.83	31.39-34.26
Analysis for Opioid Dose Response Based on Baseline MME Dosage
Control	201	5.92	5.68-6.17	0.83	14.81	13.99-15.62	0.40	31.22	30.00-32.43	0.47
LTOT (MMEs)
≤30	100	6.09	5.70-6.48		14.82	13.69-15.96		32.27	30.59-33.96
>30 to <50	66	6.10	5.66-6.53		15.98	14.77-17.19		32.93	30.95-34.90
≥50	35	5.90	5.33-6.47		15.51	13.59-17.43		32.42	29.42-35.42
Analysis for Continuous Opioid Use or Abstinence for 12 Months
Control	132	5.58	5.27-5.89	0.02	13.76	12.75-14.78	0.05	29.56	28.08-31.03	0.002
LTOT (MMEs)	119	6.13	5.81-6.45		15.16	14.19-16.12		32.83	31.39-34.26

Abbreviations: LTOT, long-term opioid therapy; CI, confidence interval; MME, morphine milligram equivalent.
^aPain intensity was measured with a numerical rating scale (0-10). Back-related disability was measured with the Roland-Morris Disability Questionnaire (0-24). Pain impact was measured using low back pain intensity and the physical function and pain interference scales of the Patient-Reported Outcomes Measurement Information System (8-50). Higher scores represent worse outcomes on each measure. Results were computed using generalized estimating equations. Table entries represent mean results and P values for the observations reported from 3 months through 12 months, following determination of treatment group membership and participant matching.