Table 4. Regression analysis for happiness and sleep.

	AHappiness		BSleep
Parameters for simple regression	beta	P*	beta	P*
Age (y)	0.069	0.002	0.020	0.371
CSex	-0.104	<0.001	0.023	0.293
Awareness of difficulty focusing	-0.025	0.272	0.140	<0.001
Impact of difficulty focusing	0.008	0.694	0.056	0.012
Near correction	0.052	0.020	0.032	0.156
Burden with near vision	-0.066	0.003	0.115	<0.001
Burden with middle distance vision	-0.046	0.038	0.063	0.005
Burden with far vision	-0.079	<0.001	0.101	<0.001
Dry eye	-0.087	<0.001	0.163	<0.001
Happiness	-	-	-0.384	<0.001
Sleep	-0.384	<0.001	-	-
Multiple regression, Model 1: Symptoms with focusing
Age	0.082	0.002	-0.028	0.285
Sex	-0.102	<0.001	0.020	0.355
Awareness of difficulty focusing	-0.050	0.048	0.151	<0.001
Impact of difficulty focusing	-0.039	0.200	0.002	0.939
Near correction	0.053	0.052	-0.006	0.809
Multiple regression, Model 2: Burden with focusing
Age	0.079	<0.001	0.002	0.925
Sex	-0.100	<0.001	0.017	0.422
Burden with near vision	-0.068	0.010	0.110	<0.001
Burden with far vision	-0.073	0.006	0.095	<0.001

*P<0.05, Standardized partial regression coefficient. A: Subjective happiness scale (0 (unhappy)-7 (happy)), B: Pittsburg Sleep Quality Index global score (higher score refers to poor sleep), C: Men = 1, Women = 0.