Determining the feasibility of a trial to evaluate the effectiveness of phototherapy versus placebo at reducing pain during physical activity for people with knee osteoarthritis: a pilot randomized controlled trial

Table 6 Immediate effects on pain intensity and adverse effects for aggregated, active phototherapy, and placebo control groups

Visit number^a		Currnet pain intensity (0 to 10)									Adverse effects—number of participants reporting “yes” to the question “did you experience any adverse effects or side effects during the treatment today?”
		Aggregated			Active phototherapy			Placebo control			Active Phototherapy	Placebo control
		N	Mean	SD	N	Mean	SD	N	Mean	SD
Visit 2	Pre-phototherapy	19	1.68	2.11	9	1.33	1.23	10	2.00	2.71	0	0
	Post-phototherapy	19	0.84	1.30	9	0.78	1.09	10	0.90	1.52	0	0
	Post-phototherapy and exercise	19	1.68	1.53	9	1.56	1.33	10	1.80	1.75	0	0
Visit 3	Pre-phototherapy	18	2.06	2.53	9	1.78	2.54	9	2.33	2.65	0	0
	Post-phototherapy	18	1.22	2.05	9	1.11	2.26	9	1.33	1.94	0	0
	Post-phototherapy and exercise	18	1.50	1.58	9	1.22	1.79	9	1.78	1.39	0	0
Visit 5	Pre-phototherapy	15	1.20	1.37	8	1.25	1.28	7	0.43	0.79	0	0
	Post-phototherapy	15	0.40	0.74	8	0.38	0.52	7	0.00	0.00	0	0
	Post-phototherapy and exercise	15	1.07	1.22	8	0.50	1.07	7	0.86	1.22	0	0
Visit 6	Pre-phototherapy	15	0.53	0.64	8	0.38	0.52	7	0.71	0.76	0	0
	Post-phototherapy	15	0.33	0.82	8	0.50	1.07	7	0.14	0.38	0	0
	Post-phototherapy and exercise	15	0.53	0.92	8	0.50	0.76	7	0.57	1.13	0	0
Visit 7	Pre-phototherapy	15	0.47	0.64	8	0.25	0.46	7	0.71	0.76	0	0
	Post-phototherapy	15	0.13	0.35	8	0.13	0.35	7	0.14	0.38	0	0
	Post-phototherapy and exercise	15	0.87	1.25	8	0.38	0.52	7	1.43	1.62	0	0

^aVisits 1, 4, and 8 did not include pre-post measures for pain intensity. On visits 1, 4, and 8, pain intensity was measused prior to the sensitivity to physical activity (SPA) test which resulted in an increase in pain intensity immediately prior to phototherapy for most participants. Thus, the results of visits 1, 4, and 8 could not be pooled with the results from the other visits

ISSN: 2055-5784