Table 1.

The distribution of negative relative accommodation (NRA) and positive relative accommodation (PRA) in a young population by sex, age, refractive errors, and phoria.

	n	NRA(D)	PRA(D)
		Mean ± SD	Mean ± SD
Total	382	+2.08 ± 0.33	−2.92 ± 0.76
Gender
Male	102	+2.06 ± 0.36	−2.73 ± 0.89
Female	280	+2.09 ± 0.31	−3 ± 0.69
Age (years)
≤20	135	+2.10 ± 0.29	−3.00 ± 0.72
21–25	202	+2.08 ± 0.32	−2.97 ± 0.67
26–30	29	+2.10 ± 0.27	−2.96 ± 0.69
>30	16	+1.89 ± 0.62	−1.55 ± 1.04
Refractive errors
Emmetropia	185	+2.12 ± 0.26	−2.80 ± 0.68
Myopia	145	+2.00 ± 0.39	−3.09 ± 0.82
Hyperopia	52	+2.13 ± 0.30	−2.90 ± 0.77
Phoria
No	303	+2.09 ± 0.3	−2.91 ± 0.63
Yes	79	+2.06 ± 0.36	−2.94 ± 0.88
Exophoria	40	+2.08 ± 0.33	−2.87 ± 0.69
Esophoria	39	+1.99 ± 0.46	−2.69 ± 0.91

D: Diopter.

NRA: Negative relative accommodation.

PRA: Positive relative accommodation.

SD: Standard deviation