Table 2.

Adjusted effect of laughter exercise on primary outcome of OSDI score at eight weeks

Outcomes	Baseline*		Follow up		Change in OSDI†		Baseline adjusted between group difference in change in OSDI‡
	No.	Mean (SD)	No.	Mean (SD)	No.	Mean (95% CI)	Mean (95% CI)
Week 8 (end of treatment)
Per protocol analysis (n=283):
Laughter exercise group	136	35.6 (12.9)	136	25.1 (15.3)	136	−10.5 (−13.1 to −7.82)***	−1.45 (−5.08 to 2.19)
0.1% HA group	147	36.7 (14.5)	147	27.9 (17.7)	147	−8.83 (−11.7 to −6.02)***	P=0.43
Intention to treat analysis (n=299):
Laughter exercise group	149	35.9 (13.6)	149	25.9 (15.9)	149	−10.0 (−12.8 to −7.29)***	−1.32 (−4.90 to 2.26)
0.1% HA group	150	36.8 (14.4)	150	28.0 (17.6)	150	−8.79 (−11.6 to −6.03)***	P=0.47
Week 12 (end of trial)
Per protocol analysis (n=283):
Laughter exercise group	137	35.9 (13.2)	137	21.3 (14.7)	137	−14.6 (−17.2 to −11.9)***	−4.08 (−7.62 to −0.55)
0.1% HA group	146	36.5 (14.2)	146	26.4 (17.3)	146	−10.1 (−13.0 to −7.30)***	P=0.02
Intention to treat analysis (n=299):
Laughter exercise group	149	35.9 (13.6)	149	21.6 (15.1)	149	−14.3 (−17.1 to −11.5)***	−3.95 (−7.50 to −0.40)
0.1% HA group	150	36.8 (14.4)	150	26.5 (17.3)	150	−10.3 (−13.1 to −7.43)***	P=0.03

Data are mean (SD) or difference mean (95% CI).

CI=confidence interval; HA=hyaluronic acid; OSDI=ocular surface disease index; SD=standard deviation.

^*No statistically significant differences between two groups for all baseline comparisons by two sample t-test.

^†Paired t-test.

^‡Linear regression with adjusting for OSDI grade at baseline.

^***P<0.001.