A comparison of accommodation and ocular discomfort change according to display size of smart devices

BMC Ophthalmology

Table 2 Change of subjective static measurement of accommodation and other ocular parameters before and after use of smart devices

	Pre	Post Smartphone	P value^a	Difference (Pre-Post)	P value^b
	Pre	Tablet	P value^a	Difference (Pre-Post)	P value^b
NPA (cm)	5.24 ± 0.77	5.43 ± 1.19	0.018	-0.20 ± 0.54	0.044
NPA (cm)	5.24 ± 0.77	5.35 ± 1.01	0.024	-0.11 ± 0.31	0.044
NPC (cm)	10.22 ± 0.84	10.46 ± 1.33	0.010	-0.24 ± 0.60	0.033
NPC (cm)	10.22 ± 0.84	10.30 ± 1.09	0.044	-0.09 ± 0.28	0.033
Exophoria (PD)
Far	0.48 ± 1.39	0.48 ± 1.39	-	0	-
Far	0.48 ± 1.39	0.48 ± 1.39	-	0	-
Near	2.52 ± 3.90	2.26 ± 3.79	0.002	0.26 ± 0.53	0.160
Near	2.52 ± 3.90	2.30 ± 3.79	0.006	0.22 ± 0.51	0.160
tBUT (sec)	8.17 ± 3.63	7.83 ± 3.43	0.010	0.35 ± 0.87	0.299
tBUT (sec)	8.17 ± 3.63	8.00 ± 3.58	0.198	0.17 ± 0.90	0.299
Stereopsis	41.30 ± 3.41	41.96 ± 4.01	0.083	-0.65 ± 2.50	-
Stereopsis	41.30 ± 3.41	41.74 ± 3.83	0.160	-0.43 ± 2.06	-
NEI score	0.24 ± 0.64	0.30 ± 0.63	0.183	-0.07 ± 0.33	0.160
NEI score	0.24 ± 0.64	0.22 ± 0.47	0.660	0.02 ± 0.33	0.160
IOP	15.28 ± 2.73	15.50 ± 2.70	0.040	-0.22 ± 0.70	0.002
IOP	15.28 ± 2.73	14.89 ± 2.76	0.032	0.39 ± 1.20	0.002
Pupil diameter	3.85 ± 0.89	3.88 ± 0.90	0.732	-0.03 ± 0.66	0.790
Pupil diameter	3.85 ± 0.89	3.91 ± 0.78	0.569	-0.06 ± 0.66	0.790

NPA Near point accommodation, NPC Near point convergence, PD Prism diopter, tBUT Tear film break-up time, NEI National Eye Institute, IOP Intraocular pressure
^ap value by paired t-test of comparison between pre-and post-test using smart devices
^bp value by paired t-test of comparison between smart phone and tablet

ISSN: 1471-2415