TABLE 2.

Utilization of care profile among adult primary care patients with at least one incident low back pain (LBP) visit according to cost profile

Variable	Cost profile
	Low cost (n=26,457)	High cost (n=11,343)
First LBP encounter with PCP*	75.28	64.18
Follow-up time (years) to first LBP encounter*
Mean ± SD	2.54±1.08	2.59±1.07
Median	2.57	2.64
Interquartile range	1.69–3.50	1.67–3.45
Total number of encounters in year before first LBP encounter*
0–2	0.18	0.23
3–6	15.62	16.57
7–10	27.95	25.21
11–15	19.84	18.23
>15	15.84	15.80
Total opioid prescriptions in the year before the first LBP encounter*
Nonuser	93.61	89.85
1	2.25	3.12
2–4	2.49	3.98
5+	1.66	3.05
LBP diagnosis group*
I	72.47	43.71
II	10.84	11.59
IIIa	1.18	0.90
IIIb	11.78	38.48
IV	0.95	2.39
Other	2.78	2.93
Physician efficiency index*
Mean ± SD	1.3±1.47	2.05±2.87
Median	0.82	1.0
Interquartile range	0.60–1.36	0.67–2.39
Insurance information*
Commercial	43.01	39.28
Medicaid	7.60	10.80
Medicare	23.77	26.61
Worker’s company	1.04	1.97

Data presented as %.

^*Indicates statistical significance among groups. Mantel-Haenszel χ² test was used for categorical variables, and Kruskal-Wallis non-parametric test was used for continuous variables. PCP Primary care physician