ACTRN12617000697381.

Study name	Calcium supplements and 24‐hour blood pressure: a randomised, cross‐over, placebo‐controlled trial in postmenopausal women
Methods	Randomised, cross‐over, placebo‐controlled trial
Participants	Females at least 5 years postmenopause. Age > 55 years if age at menopause unknown
Interventions	0.5 grams of calcium tablets as citrate salt to be taken twice a day (once in the morning and once in the evening, 12 hours apart)
Outcomes	Difference in the change from baseline in diastolic blood pressure between day one of calcium supplementation and day one of placebo Difference in the change from baseline in systolic blood pressure between day 1 of calcium supplementation and day 1 of placebo
Starting date	17/01/2018
Contact information	Dr Sarah Bristow Faculty of Medical and Health Sciences, The University of Auckland Private Bag 92019 Auckland 1142, New Zealand +6499233773 s.bristow@auckland.ac.nz
Notes	https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=372481&isReview=true