Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Adverse effects
Systematic review	117 people with moderate skin photodamage Data from 1 RCT	Adverse effects (overall) 2/58 (3%) with tazarotene 0.01% (applied once-daily for 24 weeks) 3/58 (5%) with tretinoin 0.05% (applied once-daily for 24 weeks)	RR 1.50 95% CI 0.26 to 8.65		Not significant
Systematic review	117 people with moderate skin photodamage Data from 1 RCT	Adverse effects 0/58 (0%) with tazarotene 0.025% (applied once-daily for 24 weeks) 3/58 (5%) with tretinoin 0.05% (applied once-daily for 24 weeks)	RR 7.0 95% CI 0.37 to 132.56		Not significant
Systematic review	117 people with moderate skin photodamage Data from 1 RCT	Adverse effects 2/58 (3%) with tazarotene 0.05% (applied once-daily for 24 weeks) 3/58 (5%) with tretinoin 0.05% (applied once-daily for 24 weeks)	RR 1.50 95% CI 0.26 to 8.65		Not significant
Systematic review	117 people with moderate skin photodamage Data from 1 RCT	Adverse effects 2/58 (3%) with tazarotene 0.1% (applied once-daily for 24 weeks) 3/58 (5%) with tretinoin 0.05% (applied once-daily for 24 weeks)	RR 1.50 95% CI 0.26 to 8.65		Not significant
RCT	173 people, mean age 55 years, with Fitzpatrick skin types I–IV	Sensation of burning on the skin 15% with tazarotene 0.1% (applied once-daily in the evening for 24 weeks) 0% with tretinoin 0.05% (applied once-daily in the evening for 24 weeks) Absolute numbers not reported	Reported as significant P value not reported	Effect size not calculated	tretinoin
RCT	173 people, mean age 55 years, with Fitzpatrick skin types I–IV	Irritation 21% with tazarotene 0.1% (applied once-daily in the evening for 24 weeks) 35% with tretinoin 0.05% (applied once-daily in the evening for 24 weeks) Absolute numbers not reported	Reported as not significant P value not reported		Not significant
RCT	173 people, mean age 55 years, with Fitzpatrick skin types I–IV	Dryness 9% with tazarotene 0.1% (applied once-daily in the evening for 24 weeks) 15% with tretinoin 0.05% (applied once-daily in the evening for 24 weeks) Absolute numbers not reported	Reported as not significant P value not reported		Not significant
RCT	173 people, mean age 55 years, with Fitzpatrick skin types I–IV	Peeling 12% with tazarotene 0.1% (applied once-daily in the evening for 24 weeks) 11% with tretinoin 0.05% (applied once-daily in the evening for 24 weeks) Absolute numbers not reported	Reported as not significant P value not reported		Not significant
RCT	173 people, mean age 55 years, with Fitzpatrick skin types I–IV	Redness 10% with tazarotene 0.1% (applied once-daily in the evening for 24 weeks) 7% with tretinoin 0.05% (applied once-daily in the evening for 24 weeks) Absolute numbers not reported	Reported as not significant P value not reported		Not significant
RCT	173 people, mean age 55 years, with Fitzpatrick skin types I–IV	Erythema 3% with tazarotene 0.1% (applied once-daily in the evening for 24 weeks) 4% with tretinoin 0.05% (applied once-daily in the evening for 24 weeks) Absolute numbers not reported	Reported as not significant P value not reported		Not significant
RCT	173 people, mean age 55 years, with Fitzpatrick skin types I–IV	Stinging 3% with tazarotene 0.1% (applied once-daily in the evening for 24 weeks) 6% with tretinoin 0.05% (applied once-daily in the evening for 24 weeks) Absolute numbers not reported	Reported as not significant P value not reported		Not significant
RCT	173 people, mean age 55 years, with Fitzpatrick skin types I–IV	Itching 3% with tazarotene 0.1% (applied once-daily in the evening for 24 weeks) 4% with tretinoin 0.05% (applied once-daily in the evening for 24 weeks) Absolute numbers not reported	Reported as not significant P value not reported		Not significant