Table 2.

Overview of short-term studies on tretinoin

Reference	Study design	No. of patients	Duration	Observations in tretinoin group
Weiss et al (1988)	Randomized, Double-blind 0.1% tretinoin cream vs vehicle	30	4 months	Compaction of stratum corneum Increase in glycosamine glycans (GAGs) Improvement in fine wrinkles, coarse wrinkles, tactile roughness, sallownessa
Lever et al (1990)	Double-blind 0.05% tretinoin cream vs placebo control	20	3 months	Epidermal thickening Improvement in fine wrinklesa
Shukuwa et al (1993)	Open-label 0.05% tretinoin cream	5	1 month	Compaction of stratum corneum, Disappearance of atypia, dysplasia No significant dermal changes

Note: ^aAll observations were statistically significant compared with control group.