Table 2.

Improvements in VAS scores from baseline to follow-up visits estimated by GEE after adjusting for age, gender, and BMI.

Parameter	β	SE	95% Wald CI	p-Value
All patients (ref: baseline)
1-week	−4.700	0.138	−4.970~−4.430	<0.001
1-month	−4.600	0.145	−4.884~−4.316	<0.001
3-month	−3.925	0.134	−4.188~−3.662	<0.001
6-month	−3.525	0.146	−3.811~−3.239	<0.001
Patients with FJ pain (ref: baseline)
1-week	−4.500	0.234	−4.958~−4.042	<0.001
1-month	−4.625	0.263	−5.141~−4.109	<0.001
3-month	−3.813	0.268	−4.338~−3.287	<0.001
6-month	−3.500	0.265	−4.020~−2.980	<0.001
Patients with FJ and SIJ pain (ref: baseline)
1-week	−4.833	0.163	−5.153~−4.514	<0.001
1-month	−4.583	0.166	−4.908~−4.258	<0.001
3-month	−4.000	0.132	−4.258~−3.742	<0.001
6-month	−3.542	0.166	−3.868~−3.215	<0.001

ref: reference. β: beta value. SE: standard error. CI: confidence interval. BMI: body mass index. FJ: facet joint. SIJ: sacroiliac joint. Bold fonts indicate statistical significance.