| Methods |
Double‐blind randomized placebo‐controlled trial
Cross‐over study |
| Participants |
N = 15 patients, 14 with associated connective tissue disorder
1 dropout, 2 exclusions due to incomplete data |
| Interventions |
Study carried out in 2 treatment periods, each of 2 weeks separated by a 1‐week washout period from beginning of February to end of March
Participants given diltiazem or placebo. During second treatment period, each group crossed‐over to opposite treatment
Total study duration 5 weeks |
| Outcomes |
Subjective criteria: weekly frequency of vasospastic attacks recorded daily by participant; participant evaluation of effectiveness of study agent on 5‐point clinical scale, taking frequency, severity, and duration into account
Objective: digital rheography recorded after 5 minutes of immersion of the hands in water at 30 degrees Celsius, and after 5 minutes of immersion at 5 degrees Celsius. Digital rheography performed immediately before start of the study, on the last day of first treatment, and on the last day of second treatment |
| 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 |
| Blinding of outcome assessment (detection bias)
All outcomes |
Low risk |
Subjective participant assessment of frequency, severity, and duration of attacks and overall effectiveness of treatment |
| Incomplete outcome data (attrition bias)
All outcomes |
Unclear risk |
3/15 participants excluded (1 dropout due to side effects, 2 others with incomplete diary records excluded from analyses) |
| Selective reporting (reporting bias) |
Low risk |
None detected |
| Other bias |
Low risk |
Washout period of 1 week separating cross‐over phases |
