Table 2.

Sign test statistics, pretests and posttests, of acne grading scores (AGS) for the evaluation of clinical acne severity.

	(Posttest–Pretest) Scores
Z	−7.38
Asymptotic Significance (2-Tailed)	0.000 *

AGS: Acne Grading Scores. * Significance of differences determined by the sign test (p < 0.001).