Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Digital ulcer status
RCT	308 people with Raynaud's phenomenon and systemic sclerosis	Frequency of Raynaud's attacks (digital ulcer status) 5 to 6 weeks with iloprost (50 micrograms twice daily) with placebo Absolute results not reported	Adjusted mean difference: –0.15 P = 0.459		Not significant
RCT	107 people with a history of previous healed digital ulceration	New digital ulceration 6 to 12 months 25/52 (48%) with beraprost sodium (60 micrograms three times daily) 30/51 (59%) with placebo	OR 0.65 95% CI 0.3 to 1.4 P = 0.33		Not significant
RCT	107 people with a history of previous healed digital ulceration	Mean time to appearance of digital ulceration 160 days with beraprost sodium (60 micrograms three times daily) 105 days with placebo	P = 0.23		Not significant