Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Adverse effects
RCT	15 people in total, 9 with systemic sclerosis In review	headache 80% with nifedipine 20% with placebo Absolute numbers not reported	P = 0.003	Effect size not calculated	placebo
RCT	15 people in total, 9 with systemic sclerosis In review	Lightheadedness 33% with nifedipine 7% with placebo Absolute numbers not reported	P = 0.17		Not significant
RCT	22 people in total, 8 with systemic sclerosis In review	Adverse effects 12/22 (55%) with nifedipine 2/22 (9%) with placebo	P <0.005	Effect size not calculated	placebo
RCT	15 people in total, 7 people with systemic sclerosis In review	Adverse effects 6/15 (40%) with nifedipine 2/15 (13%) with placebo	Significance not assessed
RCT	30 people in total, 10 people with systemic sclerosis In review	Headache 4 people with nifedipine 0 people with placebo	Significance not assessed
RCT	30 people in total, 10 people with systemic sclerosis In review	Nausea 5 people with nifedipine 2 people with placebo	Significance not assessed
RCT	30 people in total, 10 people with systemic sclerosis In review	Ankle oedema 7 people with nifedipine 0 people with placebo	Significance not assessed
RCT	30 people in total, 10 people with systemic sclerosis In review	Facial flushing 5 people with nifedipine 0 people with placebo	Significance not assessed
RCT	30 people in total, 10 people with systemic sclerosis In review	Faintness 0 people with nifedipine 1 person with placebo	Significance not assessed
RCT	30 people in total, 10 people with systemic sclerosis In review	Palpitations 0 people with nifedipine 1 person with placebo	Significance not assessed