The Effectiveness of a 5% Retinoic Acid Peel Combined with Microdermabrasion for Facial Photoaging: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

Table 4

Compression of responder and nonresponder participants in both groups by sex, skin phototype, and age.

Characteristic		Microdermabrasion; with tretinoin			Microdermabrasion; with placebo
		Responder (15)	Nonresponder; (30)	value	Responder (12)	Nonresponder; (33)	value
Sex (%)	Male (12)	1 (8.3%)	11 (91.7%)	0.03	0 (0%)	12 (100%)	0.02
	Female (33)	14 (42.4%)	19 (57.6%)		12 (36.4%)	21 (63.6%)
Skin type (%)	Type II (19)	7 (36.8%)	12 (63.2%)	0.75	7 (36.8%)	12 (63.2%)	0.30
	Type III (26)	8 (30.8%)	18 (69.2%)		5 (19.2%)	21 (80.8%)
Age (Mean ± SD)		40.73 ± 8.79	53.97 ± 10.34	<0.001	38.00 ± 6.16	53.76 ± 10.20	<0.001