Figure 1.
Associations between 25(OH) vitamin D3, total 24,25(OH)2 vitamin D and VMDR. Panel (a) shows a scatterplot of the association between 25(OH) vitamin D3 and total 24,25(OH)2 vitamin D levels, including linear and natural cubic spline regression lines with green shadowed areas representing the 95% confidence bands. The association appears to be approximately linear at 25(OH) vitamin D3 concentration between 0 to 50 ng/ml, and total 24,25(OH)2 vitamin D between 0 to 4 ng/ml. Panel (b) shows the association between 25(OH) vitamin D3 and VMDR restricted to values ≤150 and a natural cubic spline regression line. Panel (c) shows a scatterplot of the association between total 24,25(OH)2 vitamin D and VMDR restricted to values ≤150 and a natural cubic spline regression line. VMDR, vitamin D metabolite diagnostic ratio