Table 1

U.S. Population with chronic spine pain using NHIS and MEPS relative to trial participants

	U.S. Population		Trial Population			Trial – US Population
	% or Mean (SD)	SE	% or Mean (SD)	SE	N	Difference	P-value	Effect Size
Age†
18 to 30	10.6%	0.004	7.0%	0.007	101	-3.6%	< 0.001	0.13
31 to 50	38.8%	0.005	32.8%	0.012	473	-6.0%	< 0.001	0.13
51 to 64	30.0%	0.005	23.5%	0.011	339	-6.6%	< 0.001	0.15
65 to 84	18.5%	0.004	35.9%	0.013	518	17.3%	< 0.001	0.40
85 and above	2.1%	0.001	0.8%	0.002	12	-1.2%	0.0013	0.11
Sex†
Male	44.4%	0.005	40.7%	0.013	588
Female	55.6%	0.005	59.3%	0.013	856	3.6%	0.009	0.07
Race†
Alaskan Native, or American Indian	1.4%	0.001	0.9%	0.002	13	-0.5%	0.15	0.05
Asian or Pacific Islander	2.0%	0.001	1.2%	0.003	17	-0.8%	0.039	0.06
Black/African American	9.6%	0.003	2.3%	0.004	33	-7.3%	< 0.001	0.33
Multiple Race	0.3%	0.001	0.1%	0.001	1	-0.2%	0.13	0.05
Other Race	0.4%	0.001	0.7%	0.002	10	0.3%	0.14	0.04
White	86.3%	0.004	94.9%	0.006	1368	8.5%	< 0.001	0.30
Ethnicity†
Hispanic	9.3%	0.003	1.3%	0.003	19	-8.0%	< 0.001	0.39
Not Hispanic	90.7%	0.003	98.7%	0.003	1419
Employment†18–64 years old
Not Employed	44.8%	0.007	19.9%	0.013	178
Employed	55.2%	0.007	80.1%	0.013	716	24.9%	< 0.001	0.54
65 years or older
Not Employed	89.9%	0.006	80.4%	0.017	426
Employed	10.1%	0.006	19.6%	0.017	104	9.6%	< 0.001	0.27
Education†
Less than high school	20.9%	0.004	1.7%	0.003	24	-19.3%	< 0.001	0.69
High school	31.5%	0.005	20.4%	0.011	291	-11.1%	< 0.001	0.25
College, no degree	19.8%	0.004	21.5%	0.011	306	1.7%	0.13	0.04
Associate or technical school	10.9%	0.003	11.9%	0.009	170	1.0%	0.26	0.03
Bachelor’s	10.8%	0.003	28.6%	0.012	407	17.8%	< 0.001	0.46
Post-graduate or professional	6.1%	0.002	15.9%	0.010	227	9.9%	< 0.001	0.32
Household Income†
$0 - $34,999	47.7%	0.006	29.5%	0.013	353	-18.2%	< 0.001	0.38
$35,000 - $74,999	31.5%	0.005	45.8%	0.014	548	14.3%	< 0.001	0.29
$75,000+	20.8%	0.005	24.7%	0.012	296	3.9%	0.002	0.09
Body Mass Index†
Underweight	0.9%	0.001	0.6%	0.002	8	-0.3%	0.17	0.03
Healthy weight	28.0%	0.005	31.9%	0.012	461	3.9%	0.002	0.09
Overweight	35.8%	0.005	36.4%	0.013	526	0.6%	0.65	0.01
Obese	35.2%	0.005	31.1%	0.012	449	-4.2%	0.002	0.09
Pain Duration†
1 year or less	9.9%	0.003	21.0%	0.011	296	11.2%	< 0.001	0.31
1 to 5 years	27.3%	0.004	32.8%	0.013	461	5.4%	< 0.001	0.12
5 to 10 years	22.0%	0.004	18.8%	0.010	265	-3.1%	0.007	0.08
Over 10 years	40.8%	0.005	27.4%	0.012	385	-13.4%	< 0.001	0.28
Radiating Pain†
No	46.8%	0.005	60.0%	0.013	866
Yes	53.2%	0.005	40.0%	0.013	578	-13.2%	< 0.001	0.27
Diabetes†
No	87.0%	0.003	93.8%	0.006	1355
Yes	13.0%	0.003	6.2%	0.006	89	-6.8%	< 0.001	0.23
Smoking†
No	68.7%	0.005	90.3%	0.008	1304
Yes	31.3%	0.005	9.7%	0.008	140	-21.6%	< 0.001	0.55
Alcohol Use†
No	39.5%	0.005	41.5%	0.014	521
Yes	60.5%	0.005	58.5%	0.014	735	-2.0%	0.18	0.04
SF-12/36 PCS*	40.5 (13.0)	0.196	43.0 (8.1)	0.216	1424	2.5	< 0.001	0.19
SF-12/36 MCS*	48.2 (11.5)	0.154	53.5 (9.1)	0.241	1424	5.3	< 0.001	0.46
QALYs*	0.69 (0.21)	0.003	0.76 (0.13)	0.004	1414	0.07	< 0.001	0.33

† Data from NHIS using 15,312 observations representative of 11,473,330 U.S. adults

*Data from MEPS using 12,679 observations representative of 15,604,791 U.S. adults

N = number; QALYs = Quality-adjusted life years; SD = standard deviation; SE = standard error