Change in lesion counts ‐ inflamed (counts)
Study	Time points	Alpha‐hydroxy acid (mean, SD)	Benzoyl peroxide (mean, SD)	P value
parallel trials
Hunt 1992	Short term ‐ lesion counts reduction	Unclear, not reported	Unclear, not reported	No difference
Hunt 1992	Medium term ‐ lesion counts reduction	Unclear, not reported	Unclear, not reported	Benzoyl peroxide was significantly better than gluconolactone at eight and twelve weeks (P < 0.05)
Hunt 1992	Long term: 12 weeks after start of treatment ‐ lesion counts reduction	Unclear, not reported	Unclear, not reported	Benzoyl peroxide was significantly better than gluconolactone at eight and twelve weeks (P< 0.05)
split‐face trials
Ilknur 2010	Long term: six months after start of treatment (number of lesions post intervention)	6.88±5.18	7.00±7.26	>0.05
Ilknur 2010	Short term (number of lesions post intervention)	10.08±5.72	8.67±4.48	>0.05
Ilknur 2010	Medium term (number of lesions post intervention)	8.29±4.50	8.88±4.81	>0.05