@article{ref1,
title="Vitamin D supplementation and falls: a trial sequential meta-analysis",
journal="Lancet diabetes and endocrinology",
year="2014",
author="Bolland, Mark J. and Grey, Andrew and Gamble, Greg D. and Reid, Ian R.",
volume="2",
number="7",
pages="573-580",
abstract="BACKGROUND: Vitamin D supplementation is often recommended to prevent falls, although vitamin D trials and meta-analyses of these trials have reported conflicting results for this outcome. We aimed to assess if there was a need for further research. <br><br>METHODS: We explored the value of doing further randomised controlled trials assessing the effects of vitamin D supplements on falls with trial sequential analysis with a risk reduction threshold of 15%. All analyses were done using the numbers of participants who had a fall in intention-to-treat analyses. Trial sequential analysis performs a cumulative meta-analysis, but reduces the risk of false-positive results from repetitive statistical testing by maintaining the overall risk of type 1 error at 5%. <br><br>FINDINGS: In 20 existing randomised controlled trials (n=29 535), the effect estimate for vitamin D with or without calcium on falls lay within the futility boundary, providing evidence that vitamin D supplementation does not alter the relative risk by 15% or more. In a sensitivity analysis using a risk reduction threshold of 10%, the effect estimate also lay within the futility boundary. In subgroup analyses using a risk reduction threshold of 15%, the effect estimate also lay within the futility boundary for trials of vitamin D supplementation (16 trials, n=22 291) and trials of vitamin D with calcium (six trials, n=9919). <br><br>INTERPRETATION: In pooled analyses, supplementation with vitamin D, with or without calcium, does not reduce falls by 15% or more. Future trials with similar designs are unlikely to alter these conclusions. At present, there is little justification for prescribing vitamin D supplements to prevent falls. FUNDING: Health Research Council of New Zealand.<p /> <p>Language: en</p>",
language="en",
issn="2213-8587",
doi="10.1016/S2213-8587(14)70068-3",
url="http://dx.doi.org/10.1016/S2213-8587(14)70068-3"
}