Table 2.

Change from baseline in WOMAC and VAS outcomes of the participants.

Endpoint	Week	Laser			Sham			Difference, 95% CI	z	P
Endpoint	Week	n	Median (Q1, Q3)	95% CI	n	Median (Q1, Q3)	95% CI	Difference, 95% CI	z	P
WOMAC pain^{^a}
	2	194	1.5 (0.1, 3.0)	1.2–1.6	179	0 (–0.6, 0.8)	0–0.2	1.4 (1.0–1.7)	–7.125	< 0.01*
	4	193	2.4 (0.9, 4.7)	2.0–2.8	177	0.1 (–0.4, 1.4)	0–0.4	2.1 (1.6–2.6)	–8.616	< 0.01*
	8	192	3.0 (0.9, 5.2)	2.4–3.5	174	–0.2 (–1.1, 1.4)	–0.4 to 0	2.8 (2.2–3.4)	–9.446	< 0.01*
	12	192	2.8 (1.0, 5.5)	2.3–3.6	174	–0.2 (–1.1, 1.4)	–0.6 to 0	3.0 (2.4–3.6)	–9.455	< 0.01*
	24	191	2.9 (1.1, 5.7)	2.2–3.6	173	–0.2 (–1.4, 1.6)	–0.6 to 0	3.0 (2.5–3.6)	–9.771	< 0.01*
WOMAC function^{^b}
	2	194	4.9 (0.3, 12.6)	3.8–6.3	179	0 (–3.7, 4.3)	–0.8 to 0.2	5.8 (4.2–7.5)	–7.048	< 0.01*
	4	193	11.2 (2.4, 21.4)	8.8–14.1	177	0.5 (–2.5, 6.0)	0 to 1.5	9.8 (7.4–12.3)	–8.188	< 0.01*
	8	192	12.5 (3.8, 25.7)	8.9–16.9	174	–0.8 (–6.2, 7.8)	–2.2 to 0	12.2 (10.5–16.2)	–9.309	< 0.01*
	12	192	14.4 (4.1, 25.3)	10.4–16.6	174	–1.6 (–7.1, 5.6)	–2.8 to 0	14.9 (12.1–17.9)	–10.147	< 0.01*
	24	191	14.7 (4.0, 25.2)	10.5–16.5	173	–0.6 (–5.7, 6.6)	–2.4 to 0	14.8 (11.9–17.6)	–10.121	< 0.01*
WOMAC stiffness^{^c}
	2	194	1.5 (0, 3.8)	1.0–2.0	179	0 (–0.6, 1.1)	0–0.1	1.4 (0.9–2.0)	–6.149	< 0.01*
	4	193	2.3 (0, 5.7)	1.7–3.0	177	0 (–0.6, 1.5)	0–0.3	2.0 (1.3–2.7)	–6.203	< 0.01*
	8	192	2.7 (0, 6.5)	2.0–3.9	174	0 (–1.4, 1.5)	–0.1 to 0	2.7 (2.0–3.6)	–7.707	< 0.01*
	12	192	2.7 (0, 6.4)	1.9–4.0	174	0 (–1.4, 1.5)	0–0	2.7 (2.0–3.6)	–7.344	< 0.01*
	24	191	3.4 (0, 6.5)	2.0–4.3	173	0 (–1.8, 1.4)	–0.3 to 0	3.1 (2.2–4.0)	–8.159	< 0.01*
VAS	2	194	15.5 (5.0, 26.0)	13.3–18.3	179	2.5 (–3.0, 11.5)	0–4.0	11.5 (9.0–14.5)	–8.017	< 0.01*
	4	193	28.5 (15.3, 41.0)	25.0–30.0	177	5.0 (0, 20.0)	2.5–7.0	20.0 (16.0–23.0)	–9.120	< 0.01*
	8	192	31.5 (20.0, 43.8)	30.0–36.0	174	5.0 (–2.5, 19.0)	2.3–10.0	24.5 (20.5–28.0)	–10.290	< 0.01*
	12	192	32.5 (20.8, 44.8)	30.0–35.5	174	3.0 (–3.0, 15.0)	1.0–6.0	26.5 (22.5–30.0)	–10.838	< 0.01*
	24	191	34.0 (22.0, 45.0)	30.0–36.5	173	3.0 (–3.5, 20.0)	0.5–6.0	26.5 (23.0–30.0)	–11.169	< 0.01*

WOMAC index score reduction = baseline – posttreatment. The Mann-Whitney U test was used. For nonnormally distributed variables, 95% bootstrap CI was calculated.
↵^aP < 0.01.
↵^bP < 0.01.
↵^cP < 0.01. VAS: visual analog scale; WOMAC: Western Ontario and McMaster Universities Osteoarthritis Index.