Table 2.

RMS of the total ocular wavefront aberration measurements before and after coffee intake.

WA	Before	After 5 minutes	After 30 minutes	After 4 hours	a p
TC	−0.10 ± 0.05	−0.12 ± 0.07	−0.12 ± 0.07	−0.13 ± 0.12	0.409
TF	−0.11 ± 0.06	−0.14 ± 0.07	−0.11 ± 0.07	−0.16 ± 0.12	0.029
TSA	−0.07 ± 0.10	−0.06 ± 0.10	−0.09 ± 0.11	−0.07 ± 0.17	0.090
HOA	0.57 ± 0.42	0.69 ± 0.61	0.66 ± 0.59	0.72 ± 0.60	0.009

^aFriedman test, p < 0.05.

RMS: root-mean-square; WA: wavefront aberrations; TC: total coma; TF: total trefoil; TSA: total spherical aberration; HOA: total higher order aberration.

Results are denoted as mean ± standard deviation.