Figure 1.

Fall prevention by dose and achieved 25(OH)D concentrations. Circles represent relative risks and error bars represent 95% confidence intervals. Trendline is based on series of effect sizes (circles). There were three trials with 800 IU D₃^{w5 w6 w7}, so the effect size for 800 IU D₃ is the pooled result from these three trials. Likewise, the effect size for 1,000 IU D₂ is the pooled result from the two trials with 1,000 IU D₂^{w3 w4}. We have listed the same dose D₂ and D₃ separately in the graph to account for their potential different impact on fall reduction. As there were two data points from the Broe et al. [37] trial that reached 48 nmol/L ^w1, two trials that reached 60 nmol/L ^{w1 w3} and two trials that reached 66 nmol/L ^{w6 w7}, we pooled each of the sets. On the basis of visual inspection of Figure 1, the benefits of vitamin D for fall risk started at a dose of 700 IU a day. Reproduced from Bischoff-Ferrari et al. [35], with permission from BMJ Publishing Group Ltd.