Sauza 1984.

Methods	Parallel double‐blind randomized controlled trial
Participants	25 patients entering the trial, 18 completing the 10‐week study 17/18 completing the trial female Mean age 41 years, range 24 to 71 Only 1 with primary Raynaud's, 17 with secondary Raynaud's, 10 with recurrent digital pitting scars, none given vasodilators for at least 2 weeks before start of the study
Interventions	10 given nifedipine (30 mg to 60 mg/d) 8 given matching placebo
Outcomes	Number of Raynaud's attacks during previous 2 weeks Intensity of attacks Side effects Improvements
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Evidence insufficient for judgement of risk
Allocation concealment (selection bias)	Unclear risk	Evidence insufficient for judgement of risk
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Double‐blind study
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Participant subjective assessments
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	18/25 completing the 10‐week trial (7 exclusions due to compliance issues, failure to attend follow‐up appointments, or modifications in treatment programs)
Selective reporting (reporting bias)	Low risk	None detected
Other bias	Low risk	Two groups with similar baseline characteristics