Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Psoriasis severity
RCT 3-armed trial	38 people with mild to moderate chronic stable plaque psoriasis	Median modified Psoriasis Area and Severity Index (PASI) score 3.9 with UVA 4.2 with placebo (visible light)	P = 0.04	Effect size not calculated	UVA